From 240ddd65e66c3bdcc9fed29f222d15c201daa9d7 Mon Sep 17 00:00:00 2001
From: zer0sub <zer0.sub@protonmail.com>
Date: Sun, 12 May 2019 18:15:23 +0200
Subject: [PATCH] Add statements debug sql support.

---
 sqlbuilder/alias.go                 |   2 +-
 sqlbuilder/bool_expression_test.go  |  25 +-
 sqlbuilder/clause.go                | 141 ++++--
 sqlbuilder/column.go                |  25 +-
 sqlbuilder/delete_statement.go      |  38 +-
 sqlbuilder/delete_statement_test.go |   8 +-
 sqlbuilder/execution/execution.go   |   4 +-
 sqlbuilder/expression.go            |   2 +-
 sqlbuilder/expression_table.go      |  11 +-
 sqlbuilder/func_expression.go       |  15 +-
 sqlbuilder/insert_statement.go      |  43 +-
 sqlbuilder/insert_statement_test.go |  40 +-
 sqlbuilder/lock_statement.go        |  20 +-
 sqlbuilder/lock_statement_test.go   |   8 +-
 sqlbuilder/numeric_expression.go    |   4 +-
 sqlbuilder/select_statement.go      |  92 ++--
 sqlbuilder/set_statement.go         |  31 +-
 sqlbuilder/set_statement_test.go    |  69 ++-
 sqlbuilder/statement.go             |  23 +-
 sqlbuilder/statement_test.go        |  14 +-
 sqlbuilder/table.go                 |  14 +-
 sqlbuilder/update_statement.go      |  29 +-
 sqlbuilder/update_statement_test.go |  17 +-
 sqlbuilder/utils.go                 |   8 +-
 tests/insert_test.go                |   9 +-
 tests/select_test.go                | 658 ++++++++++++++++++----------
 tests/test_util.go                  |  89 ++++
 27 files changed, 1013 insertions(+), 426 deletions(-)
 create mode 100644 tests/test_util.go

diff --git a/sqlbuilder/alias.go b/sqlbuilder/alias.go
index 686014b..1aae3fe 100644
--- a/sqlbuilder/alias.go
+++ b/sqlbuilder/alias.go
@@ -20,7 +20,7 @@ func (a *Alias) serializeForProjection(statement statementType, out *queryData)
 		return err
 	}
 
-	out.writeString(" AS \"" + a.alias + "\"")
+	out.writeString(`AS "` + a.alias + `"`)
 
 	return nil
 }
diff --git a/sqlbuilder/bool_expression_test.go b/sqlbuilder/bool_expression_test.go
index eb968ad..457e5de 100644
--- a/sqlbuilder/bool_expression_test.go
+++ b/sqlbuilder/bool_expression_test.go
@@ -1,6 +1,7 @@
 package sqlbuilder
 
 import (
+	"fmt"
 	"gotest.tools/assert"
 	"testing"
 )
@@ -118,8 +119,17 @@ func TestExists(t *testing.T) {
 	out := queryData{}
 	err := query.serialize(select_statement, &out)
 
+	fmt.Println(out.buff.String())
+
 	assert.NilError(t, err)
-	assert.Equal(t, out.buff.String(), "EXISTS (SELECT $1 FROM db.table2 WHERE table1.col1 = table2.col3)")
+
+	expectedSql :=
+		`EXISTS (
+     SELECT $1
+     FROM db.table2
+     WHERE table1.col1 = table2.col3
+)`
+	assert.Equal(t, out.buff.String(), expectedSql)
 }
 
 func TestIn(t *testing.T) {
@@ -129,7 +139,11 @@ func TestIn(t *testing.T) {
 	err := query.serialize(select_statement, &out)
 
 	assert.NilError(t, err)
-	assert.Equal(t, out.buff.String(), `$1 IN (SELECT table1.col1 AS "table1.col1" FROM db.table1)`)
+	fmt.Println(out.buff.String())
+	assert.Equal(t, out.buff.String(), `$1 IN (
+     SELECT table1.col1 AS "table1.col1"
+     FROM db.table1
+)`)
 
 	query2 := ROW(Literal(12), table1Col1).IN(table2.SELECT(table2Col3, table3Col1))
 
@@ -137,5 +151,10 @@ func TestIn(t *testing.T) {
 	err = query2.serialize(select_statement, &out)
 
 	assert.NilError(t, err)
-	assert.Equal(t, out.buff.String(), `(ROW($1, table1.col1) IN (SELECT table2.col3 AS "table2.col3", table3.col1 AS "table3.col1" FROM db.table2))`)
+	fmt.Println(out.buff.String())
+	assert.Equal(t, out.buff.String(), `(ROW($1, table1.col1) IN (
+     SELECT table2.col3 AS "table2.col3",
+          table3.col1 AS "table3.col1"
+     FROM db.table2
+))`)
 }
diff --git a/sqlbuilder/clause.go b/sqlbuilder/clause.go
index 5df2d40..a8d73e5 100644
--- a/sqlbuilder/clause.go
+++ b/sqlbuilder/clause.go
@@ -2,7 +2,6 @@ package sqlbuilder
 
 import (
 	"bytes"
-	"errors"
 	"strconv"
 )
 
@@ -13,6 +12,9 @@ type clause interface {
 type queryData struct {
 	buff bytes.Buffer
 	args []interface{}
+
+	lastChar byte
+	ident    int
 }
 
 type statementType string
@@ -26,48 +28,125 @@ const (
 	lock_statement   statementType = "LOCK"
 )
 
+const defaultIdent = 5
+
+func (q *queryData) increaseIdent() {
+	q.ident += defaultIdent
+}
+
+func (q *queryData) decreaseIdent() {
+	if q.ident < defaultIdent {
+		q.ident = 0
+	}
+
+	q.ident -= defaultIdent
+}
+
 func (q *queryData) writeProjection(statement statementType, projections []projection) error {
-	return serializeProjectionList(statement, projections, q)
+	q.increaseIdent()
+	err := serializeProjectionList(statement, projections, q)
+	q.decreaseIdent()
+	return err
+}
+
+func (q *queryData) writeFrom(statement statementType, table tableInterface) error {
+	q.nextLine()
+	q.writeString("FROM")
+
+	q.increaseIdent()
+	err := table.serialize(statement, q)
+	q.decreaseIdent()
+
+	return err
 }
 
 func (q *queryData) writeWhere(statement statementType, where expression) error {
-	q.writeString(" WHERE ")
-	return where.serialize(statement, q)
+	q.nextLine()
+	q.writeString("WHERE")
+
+	q.increaseIdent()
+	err := where.serialize(statement, q)
+	q.decreaseIdent()
+
+	return err
 }
 
 func (q *queryData) writeGroupBy(statement statementType, groupBy []groupByClause) error {
-	q.writeString(" GROUP BY ")
+	q.nextLine()
+	q.writeString("GROUP BY")
 
-	return serializeGroupByClauseList(statement, groupBy, q)
+	q.increaseIdent()
+	err := serializeGroupByClauseList(statement, groupBy, q)
+	q.decreaseIdent()
+
+	return err
 }
 
 func (q *queryData) writeOrderBy(statement statementType, orderBy []orderByClause) error {
-	q.writeString(" ORDER BY ")
-	return serializeOrderByClauseList(statement, orderBy, q)
+	q.nextLine()
+	q.writeString("ORDER BY")
+
+	q.increaseIdent()
+	err := serializeOrderByClauseList(statement, orderBy, q)
+	q.decreaseIdent()
+
+	return err
 }
 
 func (q *queryData) writeHaving(statement statementType, having expression) error {
-	q.writeString(" HAVING ")
-	return having.serialize(statement, q)
+	q.nextLine()
+	q.writeString("HAVING")
+
+	q.increaseIdent()
+	err := having.serialize(statement, q)
+	q.decreaseIdent()
+
+	return err
+}
+
+func (q *queryData) nextLine() {
+	q.write([]byte{'\n'})
+	q.write(bytes.Repeat([]byte{' '}, q.ident))
 }
 
 func (q *queryData) write(data []byte) {
+	if len(data) == 0 {
+		return
+	}
+
+	if !isPreSeparator(q.lastChar) && !isPostSeparator(data[0]) && q.buff.Len() > 0 {
+		q.buff.WriteByte(' ')
+	}
+
 	q.buff.Write(data)
+	q.lastChar = data[len(data)-1]
+}
+
+func isPreSeparator(b byte) bool {
+	return b == ' ' || b == '.' || b == ',' || b == '(' || b == '\n'
+}
+
+func isPostSeparator(b byte) bool {
+	return b == ' ' || b == '.' || b == ',' || b == ')' || b == '\n'
 }
 
 func (q *queryData) writeString(str string) {
-	q.buff.WriteString(str)
+	q.write([]byte(str))
 }
 
 func (q *queryData) writeByte(b byte) {
-	q.buff.WriteByte(b)
+	q.write([]byte{b})
+}
+
+func (q *queryData) finalize() (string, []interface{}) {
+	return q.buff.String() + ";\n", q.args
 }
 
 func (q *queryData) insertArgument(arg interface{}) {
 	q.args = append(q.args, arg)
 	argPlaceholder := "$" + strconv.Itoa(len(q.args))
 
-	q.buff.WriteString(argPlaceholder)
+	q.writeString(argPlaceholder)
 }
 
 func (q *queryData) reset() {
@@ -75,49 +154,49 @@ func (q *queryData) reset() {
 	q.args = []interface{}{}
 }
 
-func argToString(value interface{}) (string, error) {
+func ArgToString(value interface{}) string {
 	switch bindVal := value.(type) {
 	case bool:
 		if bindVal {
-			return "TRUE", nil
+			return "TRUE"
 		} else {
-			return "FALSE", nil
+			return "FALSE"
 		}
 	case int8:
-		return strconv.FormatInt(int64(bindVal), 10), nil
+		return strconv.FormatInt(int64(bindVal), 10)
 	case int:
-		return strconv.FormatInt(int64(bindVal), 10), nil
+		return strconv.FormatInt(int64(bindVal), 10)
 	case int16:
-		return strconv.FormatInt(int64(bindVal), 10), nil
+		return strconv.FormatInt(int64(bindVal), 10)
 	case int32:
-		return strconv.FormatInt(int64(bindVal), 10), nil
+		return strconv.FormatInt(int64(bindVal), 10)
 	case int64:
-		return strconv.FormatInt(int64(bindVal), 10), nil
+		return strconv.FormatInt(int64(bindVal), 10)
 
 	case uint8:
-		return strconv.FormatUint(uint64(bindVal), 10), nil
+		return strconv.FormatUint(uint64(bindVal), 10)
 	case uint:
-		return strconv.FormatUint(uint64(bindVal), 10), nil
+		return strconv.FormatUint(uint64(bindVal), 10)
 	case uint16:
-		return strconv.FormatUint(uint64(bindVal), 10), nil
+		return strconv.FormatUint(uint64(bindVal), 10)
 	case uint32:
-		return strconv.FormatUint(uint64(bindVal), 10), nil
+		return strconv.FormatUint(uint64(bindVal), 10)
 	case uint64:
-		return strconv.FormatUint(uint64(bindVal), 10), nil
+		return strconv.FormatUint(uint64(bindVal), 10)
 
 	case float32:
-		return strconv.FormatFloat(float64(bindVal), 'f', -1, 64), nil
+		return strconv.FormatFloat(float64(bindVal), 'f', -1, 64)
 	case float64:
-		return strconv.FormatFloat(float64(bindVal), 'f', -1, 64), nil
+		return strconv.FormatFloat(float64(bindVal), 'f', -1, 64)
 
 	case string:
-		return bindVal, nil
+		return `'` + bindVal + `'`
 	case []byte:
-		return string(bindVal), nil
+		return string(bindVal)
 		//TODO: implement
 	//case time.Time:
 	//	return bindVal.String())
 	default:
-		return "", errors.New("Unsupported literal type. ")
+		return "[Unknown type]"
 	}
 }
diff --git a/sqlbuilder/column.go b/sqlbuilder/column.go
index 0738b88..6f2d71b 100644
--- a/sqlbuilder/column.go
+++ b/sqlbuilder/column.go
@@ -79,17 +79,16 @@ func (c *baseColumn) DefaultAlias() projection {
 
 func (c *baseColumn) serializeAsOrderBy(statement statementType, out *queryData) error {
 	if statement == set_statement {
-		// set statement (UNION, EXCEPT ...) can reference only select projections in order by clause
-		out.writeString(`"`)
+		// set Statement (UNION, EXCEPT ...) can reference only select projections in order by clause
+		columnRef := ""
 
 		if c.tableName != "" {
-			out.writeString(c.tableName)
-			out.writeString(".")
+			columnRef += c.tableName + "."
 		}
 
-		out.writeString(c.name)
+		columnRef += c.name
 
-		out.writeString(`"`)
+		out.writeString(`"` + columnRef + `"`)
 
 		return nil
 	}
@@ -98,22 +97,26 @@ func (c *baseColumn) serializeAsOrderBy(statement statementType, out *queryData)
 }
 
 func (c baseColumn) serialize(statement statementType, out *queryData) error {
+
+	columnRef := ""
+
 	if c.tableName != "" {
-		out.writeString(c.tableName)
-		out.writeString(".")
+		columnRef += c.tableName + "."
 	}
 
 	wrapColumnName := strings.Contains(c.name, ".")
 
 	if wrapColumnName {
-		out.writeString(`"`)
+		columnRef += `"`
 	}
 
-	out.writeString(c.name)
+	columnRef += c.name
 
 	if wrapColumnName {
-		out.writeString(`"`)
+		columnRef += `"`
 	}
 
+	out.writeString(columnRef)
+
 	return nil
 }
diff --git a/sqlbuilder/delete_statement.go b/sqlbuilder/delete_statement.go
index 6f071a5..54dcef6 100644
--- a/sqlbuilder/delete_statement.go
+++ b/sqlbuilder/delete_statement.go
@@ -7,7 +7,7 @@ import (
 )
 
 type deleteStatement interface {
-	statement
+	Statement
 
 	WHERE(expression boolExpression) deleteStatement
 }
@@ -28,28 +28,44 @@ func (d *deleteStatementImpl) WHERE(expression boolExpression) deleteStatement {
 	return d
 }
 
-func (d *deleteStatementImpl) Sql() (query string, args []interface{}, err error) {
-	queryData := &queryData{}
-
-	queryData.writeString("DELETE FROM ")
+func (d *deleteStatementImpl) serializeImpl(out *queryData) error {
+	out.nextLine()
+	out.writeString("DELETE FROM")
 
 	if d.table == nil {
-		return "", nil, errors.New("nil tableName.")
+		return errors.New("nil tableName.")
 	}
 
-	if err = d.table.serialize(delete_statement, queryData); err != nil {
-		return
+	if err := d.table.serialize(delete_statement, out); err != nil {
+		return err
 	}
 
 	if d.where == nil {
-		return "", nil, errors.New("Deleting without a WHERE clause.")
+		return errors.New("Deleting without a WHERE clause.")
 	}
 
-	if err = queryData.writeWhere(delete_statement, d.where); err != nil {
+	if err := out.writeWhere(delete_statement, d.where); err != nil {
+		return err
+	}
+
+	return nil
+}
+
+func (d *deleteStatementImpl) Sql() (query string, args []interface{}, err error) {
+	queryData := &queryData{}
+
+	err = d.serializeImpl(queryData)
+
+	if err != nil {
 		return
 	}
 
-	return queryData.buff.String() + ";", queryData.args, nil
+	query, args = queryData.finalize()
+	return
+}
+
+func (d *deleteStatementImpl) DebugSql() (query string, err error) {
+	return DebugSql(d)
 }
 
 func (u *deleteStatementImpl) Query(db types.Db, destination interface{}) error {
diff --git a/sqlbuilder/delete_statement_test.go b/sqlbuilder/delete_statement_test.go
index 24e3fc9..c95a340 100644
--- a/sqlbuilder/delete_statement_test.go
+++ b/sqlbuilder/delete_statement_test.go
@@ -1,6 +1,7 @@
 package sqlbuilder
 
 import (
+	"fmt"
 	"gotest.tools/assert"
 	"testing"
 )
@@ -14,5 +15,10 @@ func TestDeleteWithWhere(t *testing.T) {
 	sql, _, err := table1.DELETE().WHERE(table1Col1.EqL(1)).Sql()
 	assert.NilError(t, err)
 
-	assert.Equal(t, sql, "DELETE FROM db.table1 WHERE table1.col1 = $1;")
+	fmt.Println(sql)
+	expectedSql := `
+DELETE FROM db.table1
+WHERE table1.col1 = $1;
+`
+	assert.Equal(t, sql, expectedSql)
 }
diff --git a/sqlbuilder/execution/execution.go b/sqlbuilder/execution/execution.go
index 7cb44b1..84880b9 100644
--- a/sqlbuilder/execution/execution.go
+++ b/sqlbuilder/execution/execution.go
@@ -543,8 +543,8 @@ func isDbBaseType(objType reflect.Type) bool {
 	typeStr := objType.String()
 
 	switch typeStr {
-	case "string", "int32", "int16", "float32", "float64", "time.Time", "bool", "[]byte", "[]uint8",
-		"*string", "*int32", "*int16", "*float32", "*float64", "*time.Time", "*bool", "*[]byte", "*[]uint8":
+	case "string", "int", "int32", "int16", "float32", "float64", "time.Time", "bool", "[]byte", "[]uint8",
+		"*string", "*int", "*int32", "*int16", "*float32", "*float64", "*time.Time", "*bool", "*[]byte", "*[]uint8":
 		return true
 	}
 
diff --git a/sqlbuilder/expression.go b/sqlbuilder/expression.go
index a06382a..4e55fe2 100644
--- a/sqlbuilder/expression.go
+++ b/sqlbuilder/expression.go
@@ -30,7 +30,7 @@ func (e *expressionInterfaceImpl) IN(subQuery selectStatement) boolExpression {
 }
 
 func (e *expressionInterfaceImpl) NOT_IN(subQuery selectStatement) boolExpression {
-	return newBinaryBoolExpression(e.parent, subQuery, "NOT_IN")
+	return newBinaryBoolExpression(e.parent, subQuery, "NOT IN")
 }
 
 func (e *expressionInterfaceImpl) AS(alias string) projection {
diff --git a/sqlbuilder/expression_table.go b/sqlbuilder/expression_table.go
index b68f899..147c744 100644
--- a/sqlbuilder/expression_table.go
+++ b/sqlbuilder/expression_table.go
@@ -10,7 +10,6 @@ type expressionTable interface {
 
 type expressionTableImpl struct {
 	statement expression
-	columns   []column
 	alias     string
 }
 
@@ -24,7 +23,7 @@ func (s *expressionTableImpl) TableName() string {
 }
 
 func (s *expressionTableImpl) Columns() []column {
-	return s.columns
+	return []column{}
 }
 
 func (s *expressionTableImpl) RefIntColumnName(name string) *IntegerColumn {
@@ -42,20 +41,20 @@ func (s *expressionTableImpl) RefIntColumn(column column) *IntegerColumn {
 }
 
 func (s *expressionTableImpl) RefStringColumn(column column) *StringColumn {
-	strColumn := NewStringColumn(column.Name(), NotNullable)
-	strColumn.setTableName(column.TableName())
+	strColumn := NewStringColumn(column.TableName()+"."+column.Name(), NotNullable)
+	strColumn.setTableName(s.alias)
 	return strColumn
 }
 
 func (s *expressionTableImpl) serialize(statement statementType, out *queryData) error {
-	out.writeString("( ")
+	//out.writeString("( ")
 	err := s.statement.serialize(statement, out)
 
 	if err != nil {
 		return err
 	}
 
-	out.writeString(" ) AS ")
+	out.writeString("AS")
 	out.writeString(s.alias)
 
 	return nil
diff --git a/sqlbuilder/func_expression.go b/sqlbuilder/func_expression.go
index 2d8c325..71b99d3 100644
--- a/sqlbuilder/func_expression.go
+++ b/sqlbuilder/func_expression.go
@@ -29,8 +29,8 @@ func newFunc(name string, expressions []expression, parent expression) *funcExpr
 }
 
 func (f *funcExpressionImpl) serialize(statement statementType, out *queryData) error {
-	out.writeString(f.name)
-	out.writeString("(")
+	out.writeString(f.name + "(")
+
 	err := serializeExpressionList(statement, f.expression, ", ", out)
 	if err != nil {
 		return err
@@ -111,7 +111,6 @@ func (c *caseExpression) serialize(statement statementType, out *queryData) erro
 	out.writeString("(CASE")
 
 	if c.expression != nil {
-		out.writeString(" ")
 		err := c.expression.serialize(statement, out)
 
 		if err != nil {
@@ -120,7 +119,7 @@ func (c *caseExpression) serialize(statement statementType, out *queryData) erro
 	}
 
 	if len(c.when) == 0 || len(c.then) == 0 {
-		return errors.New("Invalid case statement. There should be at least one when/then expression pair. ")
+		return errors.New("Invalid case Statement. There should be at least one when/then expression pair. ")
 	}
 
 	if len(c.when) != len(c.then) {
@@ -128,14 +127,14 @@ func (c *caseExpression) serialize(statement statementType, out *queryData) erro
 	}
 
 	for i, when := range c.when {
-		out.writeString(" WHEN ")
+		out.writeString("WHEN")
 		err := when.serialize(statement, out)
 
 		if err != nil {
 			return err
 		}
 
-		out.writeString(" THEN ")
+		out.writeString("THEN")
 		err = c.then[i].serialize(statement, out)
 
 		if err != nil {
@@ -144,7 +143,7 @@ func (c *caseExpression) serialize(statement statementType, out *queryData) erro
 	}
 
 	if c.els != nil {
-		out.writeString(" ELSE ")
+		out.writeString("ELSE")
 		err := c.els.serialize(statement, out)
 
 		if err != nil {
@@ -152,7 +151,7 @@ func (c *caseExpression) serialize(statement statementType, out *queryData) erro
 		}
 	}
 
-	out.writeString(" END)")
+	out.writeString("END)")
 
 	return nil
 }
diff --git a/sqlbuilder/insert_statement.go b/sqlbuilder/insert_statement.go
index 0559d1e..a61680e 100644
--- a/sqlbuilder/insert_statement.go
+++ b/sqlbuilder/insert_statement.go
@@ -10,9 +10,9 @@ import (
 )
 
 type insertStatement interface {
-	statement
+	Statement
 
-	// Add a row of values to the insert statement.
+	// Add a row of values to the insert Statement.
 	VALUES(values ...interface{}) insertStatement
 	// Map or stracture mapped to column names
 	VALUES_MAPPING(data interface{}) insertStatement
@@ -48,9 +48,9 @@ func (u *insertStatementImpl) Execute(db types.Db) (res sql.Result, err error) {
 }
 
 // expression or default keyword
-func (s *insertStatementImpl) VALUES(values ...interface{}) insertStatement {
+func (i *insertStatementImpl) VALUES(values ...interface{}) insertStatement {
 	if len(values) == 0 {
-		return s
+		return i
 	}
 
 	literalRow := []clause{}
@@ -63,8 +63,8 @@ func (s *insertStatementImpl) VALUES(values ...interface{}) insertStatement {
 		}
 	}
 
-	s.rows = append(s.rows, literalRow)
-	return s
+	i.rows = append(i.rows, literalRow)
+	return i
 }
 
 func (i *insertStatementImpl) VALUES_MAPPING(data interface{}) insertStatement {
@@ -121,13 +121,19 @@ func (i *insertStatementImpl) addError(err string) {
 	i.errors = append(i.errors, err)
 }
 
+func (i *insertStatementImpl) DebugSql() (query string, err error) {
+	return DebugSql(i)
+}
+
 func (s *insertStatementImpl) Sql() (sql string, args []interface{}, err error) {
 	if len(s.errors) > 0 {
 		return "", nil, errors.New("sql builder errors: " + strings.Join(s.errors, ", "))
 	}
 
 	queryData := &queryData{}
-	queryData.writeString("INSERT INTO ")
+
+	queryData.nextLine()
+	queryData.writeString("INSERT INTO")
 
 	if s.table == nil {
 		return "", nil, errors.Newf("nil tableName.")
@@ -135,12 +141,14 @@ func (s *insertStatementImpl) Sql() (sql string, args []interface{}, err error)
 
 	err = s.table.serialize(insert_statement, queryData)
 
+	queryData.writeByte(' ')
+
 	if err != nil {
 		return "", nil, err
 	}
 
 	if len(s.columns) > 0 {
-		queryData.writeString(" (")
+		queryData.writeString("(")
 
 		err = serializeColumnList(insert_statement, s.columns, queryData)
 
@@ -148,7 +156,7 @@ func (s *insertStatementImpl) Sql() (sql string, args []interface{}, err error)
 			return "", nil, err
 		}
 
-		queryData.writeString(") ")
+		queryData.writeString(")")
 	}
 
 	if len(s.rows) == 0 && s.query == nil {
@@ -160,12 +168,17 @@ func (s *insertStatementImpl) Sql() (sql string, args []interface{}, err error)
 	}
 
 	if len(s.rows) > 0 {
-		queryData.writeString("VALUES (")
+		queryData.writeString("VALUES")
+
 		for row_i, row := range s.rows {
 			if row_i > 0 {
-				queryData.writeString(", (")
+				queryData.writeString(",")
 			}
 
+			queryData.increaseIdent()
+			queryData.nextLine()
+			queryData.writeString("(")
+
 			if len(row) != len(s.columns) {
 				return "", nil, errors.New("# of values does not match # of columns.")
 			}
@@ -177,6 +190,7 @@ func (s *insertStatementImpl) Sql() (sql string, args []interface{}, err error)
 			}
 
 			queryData.writeByte(')')
+			queryData.decreaseIdent()
 		}
 	}
 
@@ -189,7 +203,8 @@ func (s *insertStatementImpl) Sql() (sql string, args []interface{}, err error)
 	}
 
 	if len(s.returning) > 0 {
-		queryData.writeString(" RETURNING ")
+		queryData.nextLine()
+		queryData.writeString("RETURNING")
 
 		err = queryData.writeProjection(insert_statement, s.returning)
 
@@ -198,7 +213,7 @@ func (s *insertStatementImpl) Sql() (sql string, args []interface{}, err error)
 		}
 	}
 
-	queryData.writeByte(';')
+	sql, args = queryData.finalize()
 
-	return queryData.buff.String(), queryData.args, nil
+	return
 }
diff --git a/sqlbuilder/insert_statement_test.go b/sqlbuilder/insert_statement_test.go
index 2f6df0c..c3c8949 100644
--- a/sqlbuilder/insert_statement_test.go
+++ b/sqlbuilder/insert_statement_test.go
@@ -29,7 +29,10 @@ func TestInsertColumnLengthMismatch(t *testing.T) {
 func TestInsertNilValue(t *testing.T) {
 	query, args, err := table1.INSERT(table1Col1).VALUES(nil).Sql()
 
-	assert.Equal(t, query, "INSERT INTO db.table1 (col1) VALUES ($1);")
+	assert.Equal(t, query, `
+INSERT INTO db.table1 (col1) VALUES
+     ($1);
+`)
 	assert.Equal(t, len(args), 1)
 	assert.NilError(t, err)
 }
@@ -44,7 +47,10 @@ func TestInsertSingleValue(t *testing.T) {
 	sql, _, err := table1.INSERT(table1Col1).VALUES(1).Sql()
 	assert.NilError(t, err)
 
-	assert.Equal(t, sql, "INSERT INTO db.table1 (col1) VALUES ($1);")
+	assert.Equal(t, sql, `
+INSERT INTO db.table1 (col1) VALUES
+     ($1);
+`)
 }
 
 func TestInsertDate(t *testing.T) {
@@ -53,7 +59,10 @@ func TestInsertDate(t *testing.T) {
 	sql, _, err := table1.INSERT(table1Col4).VALUES(date).Sql()
 	assert.NilError(t, err)
 
-	assert.Equal(t, sql, "INSERT INTO db.table1 (col4) VALUES ($1);")
+	assert.Equal(t, sql, `
+INSERT INTO db.table1 (col4) VALUES
+     ($1);
+`)
 }
 
 func TestInsertMultipleValues(t *testing.T) {
@@ -63,7 +72,14 @@ func TestInsertMultipleValues(t *testing.T) {
 	sql, _, err := stmt.Sql()
 	assert.NilError(t, err)
 
-	assert.Equal(t, sql, "INSERT INTO db.table1 (col1,col2,col3) VALUES ($1, $2, $3);")
+	fmt.Println(sql)
+
+	expectedSql := `
+INSERT INTO db.table1 (col1,col2,col3) VALUES
+     ($1, $2, $3);
+`
+
+	assert.Equal(t, sql, expectedSql)
 }
 
 func TestInsertMultipleRows(t *testing.T) {
@@ -75,7 +91,16 @@ func TestInsertMultipleRows(t *testing.T) {
 	sql, _, err := stmt.Sql()
 	assert.NilError(t, err)
 
-	assert.Equal(t, sql, "INSERT INTO db.table1 (col1,col2) VALUES ($1, $2), ($3, $4), ($5, $6);")
+	fmt.Println(sql)
+
+	expectedSql := `
+INSERT INTO db.table1 (col1,col2) VALUES
+     ($1, $2),
+     ($3, $4),
+     ($5, $6);
+`
+
+	assert.Equal(t, sql, expectedSql)
 }
 
 func TestInsertValuesFromModel(t *testing.T) {
@@ -98,7 +123,10 @@ func TestInsertValuesFromModel(t *testing.T) {
 
 	fmt.Println(sql)
 
-	assert.Equal(t, sql, `INSERT INTO db.table1 (col1,col2) VALUES ($1, $2);`)
+	assert.Equal(t, sql, `
+INSERT INTO db.table1 (col1,col2) VALUES
+     ($1, $2);
+`)
 }
 
 func TestInsertValuesFromModelColumnMismatch(t *testing.T) {
diff --git a/sqlbuilder/lock_statement.go b/sqlbuilder/lock_statement.go
index 2f5cb8d..d3251b4 100644
--- a/sqlbuilder/lock_statement.go
+++ b/sqlbuilder/lock_statement.go
@@ -20,7 +20,7 @@ const (
 )
 
 type lockStatement interface {
-	statement
+	Statement
 
 	IN(lockMode lockMode) lockStatement
 	NOWAIT() lockStatement
@@ -48,9 +48,13 @@ func (l *lockStatementImpl) NOWAIT() lockStatement {
 	return l
 }
 
+func (l *lockStatementImpl) DebugSql() (query string, err error) {
+	return DebugSql(l)
+}
+
 func (l *lockStatementImpl) Sql() (query string, args []interface{}, err error) {
 	if l == nil {
-		return "", nil, errors.New("nil statement.")
+		return "", nil, errors.New("nil Statement.")
 	}
 
 	if len(l.tables) == 0 {
@@ -59,7 +63,8 @@ func (l *lockStatementImpl) Sql() (query string, args []interface{}, err error)
 
 	out := &queryData{}
 
-	out.writeString("LOCK TABLE ")
+	out.nextLine()
+	out.writeString("LOCK TABLE")
 
 	for i, table := range l.tables {
 		if i > 0 {
@@ -74,16 +79,17 @@ func (l *lockStatementImpl) Sql() (query string, args []interface{}, err error)
 	}
 
 	if l.lockMode != "" {
-		out.writeString(" IN ")
+		out.writeString("IN")
 		out.writeString(string(l.lockMode))
-		out.writeString(" MODE")
+		out.writeString("MODE")
 	}
 
 	if l.nowait {
-		out.writeString(" NOWAIT")
+		out.writeString("NOWAIT")
 	}
 
-	return out.buff.String(), out.args, nil
+	query, args = out.finalize()
+	return
 }
 
 func (l *lockStatementImpl) Query(db types.Db, destination interface{}) error {
diff --git a/sqlbuilder/lock_statement_test.go b/sqlbuilder/lock_statement_test.go
index cd625d9..af25cea 100644
--- a/sqlbuilder/lock_statement_test.go
+++ b/sqlbuilder/lock_statement_test.go
@@ -11,7 +11,9 @@ func TestLockSingleTable(t *testing.T) {
 	queryStr, _, err := lock.Sql()
 
 	assert.NilError(t, err)
-	assert.Equal(t, queryStr, `LOCK TABLE db.table1 IN ROW SHARE MODE`)
+	assert.Equal(t, queryStr, `
+LOCK TABLE db.table1 IN ROW SHARE MODE;
+`)
 }
 
 func TestLockMultipleTable(t *testing.T) {
@@ -20,5 +22,7 @@ func TestLockMultipleTable(t *testing.T) {
 	queryStr, _, err := lock.Sql()
 
 	assert.NilError(t, err)
-	assert.Equal(t, queryStr, `LOCK TABLE db.table2, db.table1 IN ACCESS EXCLUSIVE MODE NOWAIT`)
+	assert.Equal(t, queryStr, `
+LOCK TABLE db.table2, db.table1 IN ACCESS EXCLUSIVE MODE NOWAIT;
+`)
 }
diff --git a/sqlbuilder/numeric_expression.go b/sqlbuilder/numeric_expression.go
index 8a23b46..17fc60a 100644
--- a/sqlbuilder/numeric_expression.go
+++ b/sqlbuilder/numeric_expression.go
@@ -131,9 +131,9 @@ func newNumericExpressionWrap(expression expression) numericExpression {
 }
 
 func (c *numericExpressionWrapper) serialize(statement statementType, out *queryData) error {
-	out.writeString("(")
+	//out.writeString("(")
 	err := c.expression.serialize(statement, out)
-	out.writeString(")")
+	//out.writeString(")")
 
 	return err
 }
diff --git a/sqlbuilder/select_statement.go b/sqlbuilder/select_statement.go
index 6f3ed71..6b39af4 100644
--- a/sqlbuilder/select_statement.go
+++ b/sqlbuilder/select_statement.go
@@ -7,7 +7,7 @@ import (
 )
 
 type selectStatement interface {
-	statement
+	Statement
 	expression
 
 	DISTINCT() selectStatement
@@ -84,15 +84,17 @@ func (s *selectStatementImpl) FROM(table readableTable) selectStatement {
 }
 
 func (s *selectStatementImpl) serialize(statement statementType, out *queryData) error {
-
 	out.writeString("(")
 
+	out.increaseIdent()
 	err := s.serializeImpl(out)
+	out.decreaseIdent()
 
 	if err != nil {
 		return err
 	}
 
+	out.nextLine()
 	out.writeString(")")
 
 	return nil
@@ -100,10 +102,11 @@ func (s *selectStatementImpl) serialize(statement statementType, out *queryData)
 
 func (s *selectStatementImpl) serializeImpl(out *queryData) error {
 
-	out.writeString("SELECT ")
+	out.nextLine()
+	out.writeString("SELECT")
 
 	if s.distinct {
-		out.writeString("DISTINCT ")
+		out.writeString("DISTINCT")
 	}
 
 	if s.projections == nil || len(s.projections) == 0 {
@@ -116,16 +119,18 @@ func (s *selectStatementImpl) serializeImpl(out *queryData) error {
 		return err
 	}
 
-	out.writeString(" FROM ")
-
 	if s.table == nil {
 		return errors.Newf("nil tableName.")
 	}
 
-	if err := s.table.serialize(select_statement, out); err != nil {
+	if err := out.writeFrom(select_statement, s.table); err != nil {
 		return err
 	}
 
+	//if err := s.table.serialize(select_statement, out); err != nil {
+	//	return err
+	//}
+
 	if s.where != nil {
 		err := out.writeWhere(select_statement, s.where)
 
@@ -159,33 +164,42 @@ func (s *selectStatementImpl) serializeImpl(out *queryData) error {
 	}
 
 	if s.limit >= 0 {
-		out.writeString(" LIMIT ")
+		out.nextLine()
+		out.writeString("LIMIT")
 		out.insertArgument(s.limit)
 	}
 
 	if s.offset >= 0 {
-		out.writeString(" OFFSET ")
+		out.nextLine()
+		out.writeString("OFFSET")
 		out.insertArgument(s.offset)
 	}
 
 	if s.forUpdate {
-		out.writeString(" FOR UPDATE")
+		out.nextLine()
+		out.writeString("FOR UPDATE")
 	}
 
 	return nil
 }
 
-// Return the properly escaped SQL statement, against the specified database
-func (q *selectStatementImpl) Sql() (query string, args []interface{}, err error) {
+// Return the properly escaped SQL Statement, against the specified database
+func (s *selectStatementImpl) Sql() (query string, args []interface{}, err error) {
 	queryData := queryData{}
 
-	err = q.serializeImpl(&queryData)
+	err = s.serializeImpl(&queryData)
 
 	if err != nil {
 		return "", nil, err
 	}
 
-	return queryData.buff.String(), queryData.args, nil
+	query, args = queryData.finalize()
+
+	return
+}
+
+func (s *selectStatementImpl) DebugSql() (query string, err error) {
+	return DebugSql(s)
 }
 
 func (s *selectStatementImpl) AsTable(alias string) expressionTable {
@@ -195,9 +209,9 @@ func (s *selectStatementImpl) AsTable(alias string) expressionTable {
 	}
 }
 
-func (q *selectStatementImpl) WHERE(expression boolExpression) selectStatement {
-	q.where = expression
-	return q
+func (s *selectStatementImpl) WHERE(expression boolExpression) selectStatement {
+	s.where = expression
+	return s
 }
 
 func (s *selectStatementImpl) GROUP_BY(groupByClauses ...groupByClause) selectStatement {
@@ -205,46 +219,46 @@ func (s *selectStatementImpl) GROUP_BY(groupByClauses ...groupByClause) selectSt
 	return s
 }
 
-func (q *selectStatementImpl) HAVING(expression boolExpression) selectStatement {
-	q.having = expression
-	return q
+func (s *selectStatementImpl) HAVING(expression boolExpression) selectStatement {
+	s.having = expression
+	return s
 }
 
-func (q *selectStatementImpl) ORDER_BY(clauses ...orderByClause) selectStatement {
+func (s *selectStatementImpl) ORDER_BY(clauses ...orderByClause) selectStatement {
 
-	q.orderBy = clauses
+	s.orderBy = clauses
 
-	return q
+	return s
 }
 
-func (q *selectStatementImpl) OFFSET(offset int64) selectStatement {
-	q.offset = offset
-	return q
+func (s *selectStatementImpl) OFFSET(offset int64) selectStatement {
+	s.offset = offset
+	return s
 }
 
-func (q *selectStatementImpl) LIMIT(limit int64) selectStatement {
-	q.limit = limit
-	return q
+func (s *selectStatementImpl) LIMIT(limit int64) selectStatement {
+	s.limit = limit
+	return s
 }
 
-func (q *selectStatementImpl) DISTINCT() selectStatement {
-	q.distinct = true
-	return q
+func (s *selectStatementImpl) DISTINCT() selectStatement {
+	s.distinct = true
+	return s
 }
 
-func (q *selectStatementImpl) FOR_UPDATE() selectStatement {
-	q.forUpdate = true
-	return q
+func (s *selectStatementImpl) FOR_UPDATE() selectStatement {
+	s.forUpdate = true
+	return s
 }
 
 func (s *selectStatementImpl) Query(db types.Db, destination interface{}) error {
 	return Query(s, db, destination)
 }
 
-func (u *selectStatementImpl) Execute(db types.Db) (res sql.Result, err error) {
-	return Execute(u, db)
+func (s *selectStatementImpl) Execute(db types.Db) (res sql.Result, err error) {
+	return Execute(s, db)
 }
 
-func NumExp(statement selectStatement) numericExpression {
-	return newNumericExpressionWrap(statement)
+func NumExp(expression expression) numericExpression {
+	return newNumericExpressionWrap(expression)
 }
diff --git a/sqlbuilder/set_statement.go b/sqlbuilder/set_statement.go
index 1609414..a18ccee 100644
--- a/sqlbuilder/set_statement.go
+++ b/sqlbuilder/set_statement.go
@@ -13,7 +13,7 @@ const (
 )
 
 type setStatement interface {
-	statement
+	Statement
 	expression
 
 	ORDER_BY(clauses ...orderByClause) setStatement
@@ -97,8 +97,10 @@ func (us *setStatementImpl) AsTable(alias string) expressionTable {
 }
 
 func (s *setStatementImpl) serialize(statement statementType, out *queryData) error {
+
 	if s.orderBy != nil || s.limit >= 0 || s.offset >= 0 {
 		out.writeString("(")
+		out.increaseIdent()
 	}
 
 	err := s.serializeImpl(out)
@@ -108,6 +110,8 @@ func (s *setStatementImpl) serialize(statement statementType, out *queryData) er
 	}
 
 	if s.orderBy != nil || s.limit >= 0 || s.offset >= 0 {
+		out.decreaseIdent()
+		out.nextLine()
 		out.writeString(")")
 	}
 
@@ -117,18 +121,22 @@ func (s *setStatementImpl) serialize(statement statementType, out *queryData) er
 func (s *setStatementImpl) serializeImpl(out *queryData) error {
 
 	if len(s.selects) < 2 {
-		return errors.Newf("UNION statement must have at least two SELECT statements.")
+		return errors.Newf("UNION Statement must have at least two SELECT statements.")
 	}
 
+	out.nextLine()
 	out.writeString("(")
+	out.increaseIdent()
 
 	for i, selectStmt := range s.selects {
+		out.nextLine()
 		if i > 0 {
-			out.writeString(" " + s.operator + " ")
+			out.writeString(s.operator)
 
 			if s.all {
-				out.writeString(" ALL ")
+				out.writeString("ALL")
 			}
+			out.nextLine()
 		}
 
 		err := selectStmt.serialize(set_statement, out)
@@ -138,6 +146,8 @@ func (s *setStatementImpl) serializeImpl(out *queryData) error {
 		}
 	}
 
+	out.decreaseIdent()
+	out.nextLine()
 	out.writeString(")")
 
 	if s.orderBy != nil {
@@ -148,12 +158,14 @@ func (s *setStatementImpl) serializeImpl(out *queryData) error {
 	}
 
 	if s.limit >= 0 {
-		out.writeString(" LIMIT ")
+		out.nextLine()
+		out.writeString("LIMIT")
 		out.insertArgument(s.limit)
 	}
 
 	if s.offset >= 0 {
-		out.writeString(" OFFSET ")
+		out.nextLine()
+		out.writeString("OFFSET")
 		out.insertArgument(s.offset)
 	}
 
@@ -169,7 +181,12 @@ func (us *setStatementImpl) Sql() (query string, args []interface{}, err error)
 		return
 	}
 
-	return queryData.buff.String(), queryData.args, nil
+	query, args = queryData.finalize()
+	return
+}
+
+func (s *setStatementImpl) DebugSql() (query string, err error) {
+	return DebugSql(s)
 }
 
 func (s *setStatementImpl) Query(db types.Db, destination interface{}) error {
diff --git a/sqlbuilder/set_statement_test.go b/sqlbuilder/set_statement_test.go
index 91c038d..88caebe 100644
--- a/sqlbuilder/set_statement_test.go
+++ b/sqlbuilder/set_statement_test.go
@@ -1,6 +1,7 @@
 package sqlbuilder
 
 import (
+	"fmt"
 	"gotest.tools/assert"
 	"testing"
 )
@@ -28,7 +29,20 @@ func TestUnionTwoSelect(t *testing.T) {
 	).Sql()
 
 	assert.NilError(t, err)
-	assert.Equal(t, query, `((SELECT table1.col1 AS "table1.col1" FROM db.table1) UNION (SELECT table2.col3 AS "table2.col3" FROM db.table2))`)
+	fmt.Println(query)
+	assert.Equal(t, query, `
+(
+     (
+          SELECT table1.col1 AS "table1.col1"
+          FROM db.table1
+     )
+     UNION
+     (
+          SELECT table2.col3 AS "table2.col3"
+          FROM db.table2
+     )
+);
+`)
 	assert.Equal(t, len(args), 0)
 }
 
@@ -39,8 +53,26 @@ func TestUnionThreeSelect(t *testing.T) {
 		table3.SELECT(table3Col1),
 	).Sql()
 
+	fmt.Println(query)
 	assert.NilError(t, err)
-	assert.Equal(t, query, `((SELECT table1.col1 AS "table1.col1" FROM db.table1) UNION (SELECT table2.col3 AS "table2.col3" FROM db.table2) UNION (SELECT table3.col1 AS "table3.col1" FROM db.table3))`)
+	assert.Equal(t, query, `
+(
+     (
+          SELECT table1.col1 AS "table1.col1"
+          FROM db.table1
+     )
+     UNION
+     (
+          SELECT table2.col3 AS "table2.col3"
+          FROM db.table2
+     )
+     UNION
+     (
+          SELECT table3.col1 AS "table3.col1"
+          FROM db.table3
+     )
+);
+`)
 	assert.Equal(t, len(args), 0)
 }
 
@@ -51,7 +83,21 @@ func TestUnionWithOrderBy(t *testing.T) {
 	).ORDER_BY(table1Col1.ASC()).Sql()
 
 	assert.NilError(t, err)
-	assert.Equal(t, query, `((SELECT table1.col1 AS "table1.col1" FROM db.table1) UNION (SELECT table2.col3 AS "table2.col3" FROM db.table2)) ORDER BY "table1.col1" ASC`)
+	fmt.Println(query)
+	assert.Equal(t, query, `
+(
+     (
+          SELECT table1.col1 AS "table1.col1"
+          FROM db.table1
+     )
+     UNION
+     (
+          SELECT table2.col3 AS "table2.col3"
+          FROM db.table2
+     )
+)
+ORDER BY "table1.col1" ASC;
+`)
 	assert.Equal(t, len(args), 0)
 }
 
@@ -62,6 +108,21 @@ func TestUnionWithLimit(t *testing.T) {
 	).LIMIT(10).OFFSET(11).Sql()
 
 	assert.NilError(t, err)
-	assert.Equal(t, query, `((SELECT table1.col1 AS "table1.col1" FROM db.table1) UNION (SELECT table2.col3 AS "table2.col3" FROM db.table2)) LIMIT $1 OFFSET $2`)
+	fmt.Println(query)
+	assert.Equal(t, query, `
+(
+     (
+          SELECT table1.col1 AS "table1.col1"
+          FROM db.table1
+     )
+     UNION
+     (
+          SELECT table2.col3 AS "table2.col3"
+          FROM db.table2
+     )
+)
+LIMIT $1
+OFFSET $2;
+`)
 	assert.Equal(t, len(args), 2)
 }
diff --git a/sqlbuilder/statement.go b/sqlbuilder/statement.go
index e703ed9..6681013 100644
--- a/sqlbuilder/statement.go
+++ b/sqlbuilder/statement.go
@@ -3,12 +3,33 @@ package sqlbuilder
 import (
 	"database/sql"
 	"github.com/sub0zero/go-sqlbuilder/types"
+	"strconv"
+	"strings"
 )
 
-type statement interface {
+type Statement interface {
 	// String returns generated SQL as string.
 	Sql() (query string, args []interface{}, err error)
 
+	DebugSql() (query string, err error)
+
 	Query(db types.Db, destination interface{}) error
 	Execute(db types.Db) (sql.Result, error)
 }
+
+func DebugSql(statement Statement) (string, error) {
+	sql, args, err := statement.Sql()
+
+	if err != nil {
+		return "", err
+	}
+
+	debugSql := sql
+
+	for i, arg := range args {
+		argPlaceholder := "$" + strconv.Itoa(i+1)
+		debugSql = strings.Replace(debugSql, argPlaceholder, ArgToString(arg), 1)
+	}
+
+	return debugSql, nil
+}
diff --git a/sqlbuilder/statement_test.go b/sqlbuilder/statement_test.go
index 83c50f7..7ed4fd9 100644
--- a/sqlbuilder/statement_test.go
+++ b/sqlbuilder/statement_test.go
@@ -18,7 +18,7 @@ var _ = gc.Suite(&StmtSuite{})
 // NOTE: tables / columns are defined in test_utils.go
 
 //
-// SELECT statement tests
+// SELECT Statement tests
 //
 
 func (s *StmtSuite) TestSelectEmptyProjection(c *gc.C) {
@@ -233,7 +233,7 @@ func (s *StmtSuite) TestSelectDistinct(c *gc.C) {
 }
 
 //
-// INSERT statement tests
+// INSERT Statement tests
 //
 
 func (s *StmtSuite) TestInsertNoColumn(c *gc.C) {
@@ -386,7 +386,7 @@ func (s *StmtSuite) TestOnDuplicateKeyUpdateMulti(c *gc.C) {
 }
 
 //
-// LOCK/UNLOCK statement tests ================================================
+// LOCK/UNLOCK Statement tests ================================================
 //
 
 func (s *StmtSuite) TestLockStatement(c *gc.C) {
@@ -444,7 +444,7 @@ func (s *StmtSuite) TestUnionLimitWithoutOrderBy(c *gc.C) {
 	c.Assert(
 		errors.GetMessage(err),
 		gc.Equals,
-		"All inner selects in UNION statement must have LIMIT if they have ORDER BY")
+		"All inner selects in UNION Statement must have LIMIT if they have ORDER BY")
 }
 
 func (s *StmtSuite) TestUnionSelectWithMismatchedColumns(c *gc.C) {
@@ -472,7 +472,7 @@ func (s *StmtSuite) TestUnionSelectWithMismatchedColumns(c *gc.C) {
 	c.Assert(
 		errors.GetMessage(err),
 		gc.Equals,
-		"All inner selects in UNION statement must select the "+
+		"All inner selects in UNION Statement must select the "+
 			"same number of columns.  For sanity, you probably "+
 			"want to select the same tableName columns in the same "+
 			"orderBy.  If you are selecting on multiple tables, "+
@@ -481,8 +481,8 @@ func (s *StmtSuite) TestUnionSelectWithMismatchedColumns(c *gc.C) {
 
 func (s *StmtSuite) TestComplicatedUnionSelectWithWhereStatement(c *gc.C) {
 
-	// tests on outer statement: Group By, Order By, LIMIT
-	// on inner statement: AndWhere, WHERE (with AND), Order By, LIMIT
+	// tests on outer Statement: Group By, Order By, LIMIT
+	// on inner Statement: AndWhere, WHERE (with AND), Order By, LIMIT
 	select_queries := make([]selectStatement, 0, 3)
 
 	// We're not trying to write a SQL parser, so we won't warn if you do something silly like
diff --git a/sqlbuilder/table.go b/sqlbuilder/table.go
index 5bd4788..325dbcd 100644
--- a/sqlbuilder/table.go
+++ b/sqlbuilder/table.go
@@ -106,7 +106,7 @@ func (t *Table) Columns() []column {
 }
 
 // Generates the sql string for the current tableName expression.  Note: the
-// generated string may not be a valid/executable sql statement.
+// generated string may not be a valid/executable sql Statement.
 func (t *Table) serialize(statement statementType, out *queryData) error {
 	if t == nil {
 		return errors.Newf("nil tableName.")
@@ -287,17 +287,19 @@ func (t *joinTable) serialize(statement statementType, out *queryData) (err erro
 		return
 	}
 
+	out.nextLine()
+
 	switch t.join_type {
 	case INNER_JOIN:
-		out.writeString(" JOIN ")
+		out.writeString("JOIN")
 	case LEFT_JOIN:
-		out.writeString(" LEFT JOIN ")
+		out.writeString("LEFT JOIN")
 	case RIGHT_JOIN:
-		out.writeString(" RIGHT JOIN ")
+		out.writeString("RIGHT JOIN")
 	case FULL_JOIN:
-		out.writeString(" FULL JOIN ")
+		out.writeString("FULL JOIN")
 	case CROSS_JOIN:
-		out.writeString(" CROSS JOIN ")
+		out.writeString("CROSS JOIN")
 	}
 
 	if err = t.rhs.serialize(statement, out); err != nil {
diff --git a/sqlbuilder/update_statement.go b/sqlbuilder/update_statement.go
index 88a186f..7d55f8b 100644
--- a/sqlbuilder/update_statement.go
+++ b/sqlbuilder/update_statement.go
@@ -7,7 +7,7 @@ import (
 )
 
 type updateStatement interface {
-	statement
+	Statement
 
 	SET(values ...interface{}) updateStatement
 	WHERE(expression boolExpression) updateStatement
@@ -55,7 +55,8 @@ func (u *updateStatementImpl) RETURNING(projections ...projection) updateStateme
 func (u *updateStatementImpl) Sql() (sql string, args []interface{}, err error) {
 	out := &queryData{}
 
-	out.writeString("UPDATE ")
+	out.nextLine()
+	out.writeString("UPDATE")
 
 	if u.table == nil {
 		return "", nil, errors.New("nil tableName.")
@@ -69,12 +70,10 @@ func (u *updateStatementImpl) Sql() (sql string, args []interface{}, err error)
 		return "", nil, errors.New("No column updated.")
 	}
 
-	out.writeString(" SET")
+	out.writeString("SET")
 
 	if len(u.columns) > 1 {
-		out.writeString(" ( ")
-	} else {
-		out.writeString(" ")
+		out.writeString("(")
 	}
 
 	err = serializeColumnList(update_statement, u.columns, out)
@@ -84,13 +83,13 @@ func (u *updateStatementImpl) Sql() (sql string, args []interface{}, err error)
 	}
 
 	if len(u.columns) > 1 {
-		out.writeString(" )")
+		out.writeString(")")
 	}
 
-	out.writeString(" =")
+	out.writeString("=")
 
 	if len(u.updateValues) > 1 {
-		out.writeString(" (")
+		out.writeString("(")
 	}
 
 	for i, value := range u.updateValues {
@@ -106,7 +105,7 @@ func (u *updateStatementImpl) Sql() (sql string, args []interface{}, err error)
 	}
 
 	if len(u.updateValues) > 1 {
-		out.writeString(" )")
+		out.writeString(")")
 	}
 
 	if u.where == nil {
@@ -118,7 +117,8 @@ func (u *updateStatementImpl) Sql() (sql string, args []interface{}, err error)
 	}
 
 	if len(u.returning) > 0 {
-		out.writeString(" RETURNING ")
+		out.nextLine()
+		out.writeString("RETURNING")
 
 		err = serializeProjectionList(update_statement, u.returning, out)
 
@@ -127,7 +127,12 @@ func (u *updateStatementImpl) Sql() (sql string, args []interface{}, err error)
 		}
 	}
 
-	return out.buff.String(), out.args, nil
+	sql, args = out.finalize()
+	return
+}
+
+func (u *updateStatementImpl) DebugSql() (query string, err error) {
+	return DebugSql(u)
 }
 
 func (u *updateStatementImpl) Query(db types.Db, destination interface{}) error {
diff --git a/sqlbuilder/update_statement_test.go b/sqlbuilder/update_statement_test.go
index bb6dcd9..d6e9daa 100644
--- a/sqlbuilder/update_statement_test.go
+++ b/sqlbuilder/update_statement_test.go
@@ -7,19 +7,30 @@ import (
 )
 
 //
-// UPDATE statement tests =====================================================
+// UPDATE Statement tests =====================================================
 //
 
 func TestUpdate(t *testing.T) {
 	stmt := table1.UPDATE(table1Col1, table1Col2).
-		SET(table1.SELECT(table1Col2)).
-		WHERE(table1Col1.EqL(2))
+		SET(table1.SELECT(table1Col2, table2Col3)).
+		WHERE(table1Col1.EqL(2)).
+		RETURNING(table1Col1)
 
 	stmtStr, _, err := stmt.Sql()
 
 	assert.NilError(t, err)
 
 	fmt.Println(stmtStr)
+
+	assert.Equal(t, stmtStr, `
+UPDATE db.table1 SET (col1,col2) = (
+     SELECT table1.col2 AS "table1.col2",
+          table2.col3 AS "table2.col3"
+     FROM db.table1
+)
+WHERE table1.col1 = $1
+RETURNING table1.col1 AS "table1.col1";
+`)
 }
 
 //func (s *StmtSuite) TestUpdateNilColumn(c *gc.C) {
diff --git a/sqlbuilder/utils.go b/sqlbuilder/utils.go
index 1ea6f0c..859113b 100644
--- a/sqlbuilder/utils.go
+++ b/sqlbuilder/utils.go
@@ -82,8 +82,10 @@ func serializeExpressionList(statement statementType, expressions []expression,
 func serializeProjectionList(statement statementType, projections []projection, out *queryData) error {
 	for i, col := range projections {
 		if i > 0 {
-			out.writeString(", ")
+			out.writeString(",")
+			out.nextLine()
 		}
+
 		if col == nil {
 			return errors.New("projection expression is nil.")
 		}
@@ -112,7 +114,7 @@ func serializeColumnList(statement statementType, columns []column, out *queryDa
 	return nil
 }
 
-func Query(statement statement, db types.Db, destination interface{}) error {
+func Query(statement Statement, db types.Db, destination interface{}) error {
 	query, args, err := statement.Sql()
 
 	if err != nil {
@@ -122,7 +124,7 @@ func Query(statement statement, db types.Db, destination interface{}) error {
 	return execution.Query(db, query, args, destination)
 }
 
-func Execute(statement statement, db types.Db) (res sql.Result, err error) {
+func Execute(statement Statement, db types.Db) (res sql.Result, err error) {
 	query, args, err := statement.Sql()
 
 	if err != nil {
diff --git a/tests/insert_test.go b/tests/insert_test.go
index 48482fb..b6154fc 100644
--- a/tests/insert_test.go
+++ b/tests/insert_test.go
@@ -25,7 +25,14 @@ func TestInsertValues(t *testing.T) {
 
 	fmt.Println(insertQueryStr)
 
-	assert.Equal(t, insertQueryStr, `INSERT INTO test_sample.link (url,name,rel) VALUES ($1, $2, DEFAULT), ($3, $4, DEFAULT), ($5, $6, DEFAULT), ($7, $8, DEFAULT) RETURNING link.id AS "link.id";`)
+	assert.Equal(t, insertQueryStr, `
+INSERT INTO test_sample.link (url,name,rel) VALUES
+     ($1, $2, DEFAULT),
+     ($3, $4, DEFAULT),
+     ($5, $6, DEFAULT),
+     ($7, $8, DEFAULT)
+RETURNING link.id AS "link.id";
+`)
 	res, err := insertQuery.Execute(db)
 
 	assert.NilError(t, err)
diff --git a/tests/select_test.go b/tests/select_test.go
index 81c4c37..db341c8 100644
--- a/tests/select_test.go
+++ b/tests/select_test.go
@@ -2,29 +2,33 @@ package tests
 
 import (
 	"fmt"
-	"github.com/sub0zero/go-sqlbuilder/sqlbuilder"
+	. "github.com/sub0zero/go-sqlbuilder/sqlbuilder"
 	"github.com/sub0zero/go-sqlbuilder/tests/.test_files/dvd_rental/dvds/model"
 	. "github.com/sub0zero/go-sqlbuilder/tests/.test_files/dvd_rental/dvds/table"
 	"gotest.tools/assert"
-	"strings"
 	"testing"
-	"time"
 )
 
 func TestSelect_ScanToStruct(t *testing.T) {
-	actor := model.Actor{}
+	expectedSql := `
+SELECT actor.actor_id AS "actor.actor_id",
+     actor.first_name AS "actor.first_name",
+     actor.last_name AS "actor.last_name",
+     actor.last_update AS "actor.last_update"
+FROM dvds.actor
+WHERE actor.actor_id = 1
+ORDER BY actor.actor_id ASC;
+`
+
 	query := Actor.
 		SELECT(Actor.AllColumns).
+		WHERE(Actor.ActorID.EqL(1)).
 		ORDER_BY(Actor.ActorID.ASC())
 
-	queryStr, args, err := query.Sql()
+	assertQuery(t, query, expectedSql, 1)
 
-	fmt.Println(queryStr)
-
-	assert.Equal(t, queryStr, `SELECT actor.actor_id AS "actor.actor_id", actor.first_name AS "actor.first_name", actor.last_name AS "actor.last_name", actor.last_update AS "actor.last_update" FROM dvds.actor ORDER BY actor.actor_id ASC`)
-	assert.Equal(t, len(args), 0)
-
-	err = query.Query(db, &actor)
+	actor := model.Actor{}
+	err := query.Query(db, &actor)
 
 	assert.NilError(t, err)
 
@@ -39,37 +43,68 @@ func TestSelect_ScanToStruct(t *testing.T) {
 }
 
 func TestClassicSelect(t *testing.T) {
-	query := sqlbuilder.SELECT(Payment.AllColumns, Customer.AllColumns).
+	expectedSql := `
+SELECT payment.payment_id AS "payment.payment_id",
+     payment.customer_id AS "payment.customer_id",
+     payment.staff_id AS "payment.staff_id",
+     payment.rental_id AS "payment.rental_id",
+     payment.amount AS "payment.amount",
+     payment.payment_date AS "payment.payment_date",
+     customer.customer_id AS "customer.customer_id",
+     customer.store_id AS "customer.store_id",
+     customer.first_name AS "customer.first_name",
+     customer.last_name AS "customer.last_name",
+     customer.email AS "customer.email",
+     customer.address_id AS "customer.address_id",
+     customer.activebool AS "customer.activebool",
+     customer.create_date AS "customer.create_date",
+     customer.last_update AS "customer.last_update",
+     customer.active AS "customer.active"
+FROM dvds.payment
+     JOIN dvds.customer ON payment.customer_id = customer.customer_id
+ORDER BY payment.payment_id ASC
+LIMIT 30;
+`
+
+	query := SELECT(Payment.AllColumns, Customer.AllColumns).
 		FROM(Payment.INNER_JOIN(Customer, Payment.CustomerID.Eq(Customer.CustomerID))).
 		ORDER_BY(Payment.PaymentID.ASC()).
 		LIMIT(30)
 
-	queryStr, args, err := query.Sql()
-
-	assert.NilError(t, err)
-	fmt.Println(queryStr)
-	fmt.Println(args)
+	assertQuery(t, query, expectedSql, int64(30))
 
 	dest := []model.Payment{}
 
-	err = query.Query(db, &dest)
+	err := query.Query(db, &dest)
 
 	assert.NilError(t, err)
+	assert.Equal(t, len(dest), 30)
+
+	//spew.Dump(dest)
 }
 
 func TestSelect_ScanToSlice(t *testing.T) {
+	expectedSql := `
+SELECT customer.customer_id AS "customer.customer_id",
+     customer.store_id AS "customer.store_id",
+     customer.first_name AS "customer.first_name",
+     customer.last_name AS "customer.last_name",
+     customer.email AS "customer.email",
+     customer.address_id AS "customer.address_id",
+     customer.activebool AS "customer.activebool",
+     customer.create_date AS "customer.create_date",
+     customer.last_update AS "customer.last_update",
+     customer.active AS "customer.active"
+FROM dvds.customer
+ORDER BY customer.customer_id ASC;
+`
 	customers := []model.Customer{}
 
 	query := Customer.SELECT(Customer.AllColumns).ORDER_BY(Customer.CustomerID.ASC())
 
-	queryStr, args, err := query.Sql()
-	assert.NilError(t, err)
-	fmt.Println(queryStr)
+	assertQuery(t, query, expectedSql)
 
-	assert.Equal(t, queryStr, `SELECT customer.customer_id AS "customer.customer_id", customer.store_id AS "customer.store_id", customer.first_name AS "customer.first_name", customer.last_name AS "customer.last_name", customer.email AS "customer.email", customer.address_id AS "customer.address_id", customer.activebool AS "customer.activebool", customer.create_date AS "customer.create_date", customer.last_update AS "customer.last_update", customer.active AS "customer.active" FROM dvds.customer ORDER BY customer.customer_id ASC`)
-	assert.Equal(t, len(args), 0)
-
-	err = query.Query(db, &customers)
+	err := query.Query(db, &customers)
 	assert.NilError(t, err)
 
 	assert.Equal(t, len(customers), 599)
@@ -80,20 +115,48 @@ func TestSelect_ScanToSlice(t *testing.T) {
 }
 
 func TestSelectAndUnionInProjection(t *testing.T) {
+	expectedSql := `
+SELECT payment.payment_id AS "payment.payment_id",
+     (
+          SELECT customer.customer_id AS "customer.customer_id"
+          FROM dvds.customer
+          LIMIT 1
+     ),
+     (
+          (
+               (
+                    SELECT payment.payment_id AS "payment.payment_id"
+                    FROM dvds.payment
+                    LIMIT 1
+                    OFFSET 10
+               )
+               UNION
+               (
+                    SELECT payment.payment_id AS "payment.payment_id"
+                    FROM dvds.payment
+                    LIMIT 1
+                    OFFSET 2
+               )
+          )
+          LIMIT 1
+     )
+FROM dvds.payment
+LIMIT 12;
+`
 
 	query := Payment.
 		SELECT(
 			Payment.PaymentID,
 			Customer.SELECT(Customer.CustomerID).LIMIT(1),
-			sqlbuilder.UNION(Payment.SELECT(Payment.PaymentID).LIMIT(1).OFFSET(10), Payment.SELECT(Payment.PaymentID).LIMIT(1).OFFSET(2)).LIMIT(1),
+			UNION(
+				Payment.SELECT(Payment.PaymentID).LIMIT(1).OFFSET(10),
+				Payment.SELECT(Payment.PaymentID).LIMIT(1).OFFSET(2),
+			).LIMIT(1),
 		).
 		LIMIT(12)
 
-	queryStr, args, err := query.Sql()
-
-	assert.NilError(t, err)
-	fmt.Println(queryStr)
-	fmt.Println(args)
+	fmt.Println(query.Sql())
+	assertQuery(t, query, expectedSql, int64(1), int64(1), int64(10), int64(1), int64(2), int64(1), int64(12))
 }
 
 //func TestJoinQueryStruct(t *testing.T) {
@@ -122,6 +185,29 @@ func TestSelectAndUnionInProjection(t *testing.T) {
 //}
 
 func TestJoinQuerySlice(t *testing.T) {
+	expectedSql := `
+SELECT language.language_id AS "language.language_id",
+     language.name AS "language.name",
+     language.last_update AS "language.last_update",
+     film.film_id AS "film.film_id",
+     film.title AS "film.title",
+     film.description AS "film.description",
+     film.release_year AS "film.release_year",
+     film.language_id AS "film.language_id",
+     film.rental_duration AS "film.rental_duration",
+     film.rental_rate AS "film.rental_rate",
+     film.length AS "film.length",
+     film.replacement_cost AS "film.replacement_cost",
+     film.rating AS "film.rating",
+     film.last_update AS "film.last_update",
+     film.special_features AS "film.special_features",
+     film.fulltext AS "film.fulltext"
+FROM dvds.film
+     JOIN dvds.language ON film.language_id = language.language_id
+WHERE film.rating = 'NC-17'
+LIMIT 15;
+`
+
 	type FilmsPerLanguage struct {
 		Language *model.Language
 		Film     []model.Film
@@ -136,25 +222,11 @@ func TestJoinQuerySlice(t *testing.T) {
 		WHERE(Film.Rating.EqString(string(model.MpaaRating_NC17))).
 		LIMIT(15)
 
-	queryStr, args, err := query.Sql()
+	assertQuery(t, query, expectedSql, string(model.MpaaRating_NC17), int64(15))
+
+	err := query.Query(db, &filmsPerLanguage)
 
 	assert.NilError(t, err)
-	fmt.Println(queryStr)
-	assert.Equal(t, queryStr, `SELECT language.language_id AS "language.language_id", language.name AS "language.name", language.last_update AS "language.last_update", film.film_id AS "film.film_id", film.title AS "film.title", film.description AS "film.description", film.release_year AS "film.release_year", film.language_id AS "film.language_id", film.rental_duration AS "film.rental_duration", film.rental_rate AS "film.rental_rate", film.length AS "film.length", film.replacement_cost AS "film.replacement_cost", film.rating AS "film.rating", film.last_update AS "film.last_update", film.special_features AS "film.special_features", film.fulltext AS "film.fulltext" FROM dvds.film JOIN dvds.language ON film.language_id = language.language_id WHERE film.rating = $1 LIMIT $2`)
-
-	assert.Equal(t, len(args), 2)
-	assert.Equal(t, args[0], string(model.MpaaRating_NC17))
-	assert.Equal(t, args[1], int64(15))
-
-	err = query.Query(db, &filmsPerLanguage)
-
-	assert.NilError(t, err)
-
-	//fmt.Println("--------------- result --------------- ")
-	//spew.Dump(filmsPerLanguage)
-
-	//spew.Dump(filmsPerLanguage)
-
 	assert.Equal(t, len(filmsPerLanguage), 1)
 	assert.Equal(t, len(filmsPerLanguage[0].Film), limit)
 
@@ -162,8 +234,6 @@ func TestJoinQuerySlice(t *testing.T) {
 
 	assert.Equal(t, *englishFilms.Film[0].Rating, model.MpaaRating_NC17)
 
-	//spew.Dump(filmsPerLanguage)
-
 	filmsPerLanguageWithPtrs := []*FilmsPerLanguage{}
 	err = query.Query(db, &filmsPerLanguageWithPtrs)
 
@@ -187,8 +257,6 @@ func TestJoinQuerySliceWithPtrs(t *testing.T) {
 	filmsPerLanguageWithPtrs := []*FilmsPerLanguage{}
 	err := query.Query(db, &filmsPerLanguageWithPtrs)
 
-	//spew.Dump(filmsPerLanguageWithPtrs)
-
 	assert.NilError(t, err)
 	assert.Equal(t, len(filmsPerLanguageWithPtrs), 1)
 	assert.Equal(t, len(*filmsPerLanguageWithPtrs[0].Film), int(limit))
@@ -257,24 +325,42 @@ func TestSelectOrderByAscDesc(t *testing.T) {
 }
 
 func TestSelectFullJoin(t *testing.T) {
+	expectedSql := `
+SELECT customer.customer_id AS "customer.customer_id",
+     customer.store_id AS "customer.store_id",
+     customer.first_name AS "customer.first_name",
+     customer.last_name AS "customer.last_name",
+     customer.email AS "customer.email",
+     customer.address_id AS "customer.address_id",
+     customer.activebool AS "customer.activebool",
+     customer.create_date AS "customer.create_date",
+     customer.last_update AS "customer.last_update",
+     customer.active AS "customer.active",
+     address.address_id AS "address.address_id",
+     address.address AS "address.address",
+     address.address2 AS "address.address2",
+     address.district AS "address.district",
+     address.city_id AS "address.city_id",
+     address.postal_code AS "address.postal_code",
+     address.phone AS "address.phone",
+     address.last_update AS "address.last_update"
+FROM dvds.customer
+     FULL JOIN dvds.address ON customer.address_id = address.address_id
+ORDER BY customer.customer_id ASC;
+`
 	query := Customer.
 		FULL_JOIN(Address, Customer.AddressID.Eq(Address.AddressID)).
 		SELECT(Customer.AllColumns, Address.AllColumns).
 		ORDER_BY(Customer.CustomerID.ASC())
 
-	queryStr, args, err := query.Sql()
-
-	assert.NilError(t, err)
-
-	assert.Equal(t, queryStr, `SELECT customer.customer_id AS "customer.customer_id", customer.store_id AS "customer.store_id", customer.first_name AS "customer.first_name", customer.last_name AS "customer.last_name", customer.email AS "customer.email", customer.address_id AS "customer.address_id", customer.activebool AS "customer.activebool", customer.create_date AS "customer.create_date", customer.last_update AS "customer.last_update", customer.active AS "customer.active", address.address_id AS "address.address_id", address.address AS "address.address", address.address2 AS "address.address2", address.district AS "address.district", address.city_id AS "address.city_id", address.postal_code AS "address.postal_code", address.phone AS "address.phone", address.last_update AS "address.last_update" FROM dvds.customer FULL JOIN dvds.address ON customer.address_id = address.address_id ORDER BY customer.customer_id ASC`)
-	assert.Equal(t, len(args), 0)
+	assertQuery(t, query, expectedSql)
 
 	allCustomersAndAddress := []struct {
 		Address  *model.Address
 		Customer *model.Customer
 	}{}
 
-	err = query.Query(db, &allCustomersAndAddress)
+	err := query.Query(db, &allCustomersAndAddress)
 
 	assert.NilError(t, err)
 	assert.Equal(t, len(allCustomersAndAddress), 603)
@@ -290,21 +376,41 @@ func TestSelectFullJoin(t *testing.T) {
 }
 
 func TestSelectFullCrossJoin(t *testing.T) {
+	expectedSql := `
+SELECT customer.customer_id AS "customer.customer_id",
+     customer.store_id AS "customer.store_id",
+     customer.first_name AS "customer.first_name",
+     customer.last_name AS "customer.last_name",
+     customer.email AS "customer.email",
+     customer.address_id AS "customer.address_id",
+     customer.activebool AS "customer.activebool",
+     customer.create_date AS "customer.create_date",
+     customer.last_update AS "customer.last_update",
+     customer.active AS "customer.active",
+     address.address_id AS "address.address_id",
+     address.address AS "address.address",
+     address.address2 AS "address.address2",
+     address.district AS "address.district",
+     address.city_id AS "address.city_id",
+     address.postal_code AS "address.postal_code",
+     address.phone AS "address.phone",
+     address.last_update AS "address.last_update"
+FROM dvds.customer
+     CROSS JOIN dvds.address
+ORDER BY customer.customer_id ASC
+LIMIT 1000;
+`
 	query := Customer.
 		CROSS_JOIN(Address).
 		SELECT(Customer.AllColumns, Address.AllColumns).
 		ORDER_BY(Customer.CustomerID.ASC()).
 		LIMIT(1000)
 
-	queryStr, args, err := query.Sql()
-
-	assert.NilError(t, err)
-	assert.Equal(t, queryStr, `SELECT customer.customer_id AS "customer.customer_id", customer.store_id AS "customer.store_id", customer.first_name AS "customer.first_name", customer.last_name AS "customer.last_name", customer.email AS "customer.email", customer.address_id AS "customer.address_id", customer.activebool AS "customer.activebool", customer.create_date AS "customer.create_date", customer.last_update AS "customer.last_update", customer.active AS "customer.active", address.address_id AS "address.address_id", address.address AS "address.address", address.address2 AS "address.address2", address.district AS "address.district", address.city_id AS "address.city_id", address.postal_code AS "address.postal_code", address.phone AS "address.phone", address.last_update AS "address.last_update" FROM dvds.customer CROSS JOIN dvds.address ORDER BY customer.customer_id ASC LIMIT $1`)
-	assert.Equal(t, len(args), 1)
+	assertQuery(t, query, expectedSql, int64(1000))
 
 	customerAddresCrosJoined := []model.Customer{}
 
-	err = query.Query(db, &customerAddresCrosJoined)
+	err := query.Query(db, &customerAddresCrosJoined)
 
 	assert.Equal(t, len(customerAddresCrosJoined), 1000)
 
@@ -312,23 +418,49 @@ func TestSelectFullCrossJoin(t *testing.T) {
 }
 
 func TestSelectSelfJoin(t *testing.T) {
-
+	expectedSql := `
+SELECT f1.film_id AS "f1.film_id",
+     f1.title AS "f1.title",
+     f1.description AS "f1.description",
+     f1.release_year AS "f1.release_year",
+     f1.language_id AS "f1.language_id",
+     f1.rental_duration AS "f1.rental_duration",
+     f1.rental_rate AS "f1.rental_rate",
+     f1.length AS "f1.length",
+     f1.replacement_cost AS "f1.replacement_cost",
+     f1.rating AS "f1.rating",
+     f1.last_update AS "f1.last_update",
+     f1.special_features AS "f1.special_features",
+     f1.fulltext AS "f1.fulltext",
+     f2.film_id AS "f2.film_id",
+     f2.title AS "f2.title",
+     f2.description AS "f2.description",
+     f2.release_year AS "f2.release_year",
+     f2.language_id AS "f2.language_id",
+     f2.rental_duration AS "f2.rental_duration",
+     f2.rental_rate AS "f2.rental_rate",
+     f2.length AS "f2.length",
+     f2.replacement_cost AS "f2.replacement_cost",
+     f2.rating AS "f2.rating",
+     f2.last_update AS "f2.last_update",
+     f2.special_features AS "f2.special_features",
+     f2.fulltext AS "f2.fulltext"
+FROM dvds.film AS f1
+     JOIN dvds.film AS f2 ON (f1.film_id != f2.film_id AND f1.length = f2.length)
+ORDER BY f1.film_id ASC
+LIMIT 100;
+`
 	f1 := Film.AS("f1")
 
-	//spew.Dump(f1)
 	f2 := Film.AS("f2")
 
 	query := f1.
 		INNER_JOIN(f2, f1.FilmID.NotEq(f2.FilmID).AND(f1.Length.Eq(f2.Length))).
 		SELECT(f1.AllColumns, f2.AllColumns).
-		ORDER_BY(f1.FilmID.ASC())
+		ORDER_BY(f1.FilmID.ASC()).
+		LIMIT(100)
 
-	queryStr, args, err := query.Sql()
-	assert.Equal(t, len(args), 0)
-
-	assert.NilError(t, err)
-
-	fmt.Println(queryStr)
+	assertQuery(t, query, expectedSql, int64(100))
 
 	type F1 model.Film
 	type F2 model.Film
@@ -338,25 +470,26 @@ func TestSelectSelfJoin(t *testing.T) {
 		F2 F2
 	}{}
 
-	err = query.Query(db, &theSameLengthFilms)
+	err := query.Query(db, &theSameLengthFilms)
 
 	assert.NilError(t, err)
 
-	//spew.Dump(theSameLengthFilms[0])
-
-	assert.Equal(t, len(theSameLengthFilms), 6972)
+	assert.Equal(t, len(theSameLengthFilms), 100)
 }
 
 func TestSelectAliasColumn(t *testing.T) {
+	expectedSql := `
+SELECT f1.title AS "thesame_length_films.title1",
+     f2.title AS "thesame_length_films.title2",
+     f1.length AS "thesame_length_films.length"
+FROM dvds.film AS f1
+     JOIN dvds.film AS f2 ON (f1.film_id != f2.film_id AND f1.length = f2.length)
+ORDER BY f1.length ASC, f1.title ASC, f2.title ASC
+LIMIT 1000;
+`
 	f1 := Film.AS("f1")
 	f2 := Film.AS("f2")
 
-	type thesameLengthFilms struct {
-		Title1 string
-		Title2 string
-		Length int16
-	}
-
 	query := f1.
 		INNER_JOIN(f2, f1.FilmID.NotEq(f2.FilmID).AND(f1.Length.Eq(f2.Length))).
 		SELECT(f1.Title.AS("thesame_length_films.title1"),
@@ -365,15 +498,16 @@ func TestSelectAliasColumn(t *testing.T) {
 		ORDER_BY(f1.Length.ASC(), f1.Title.ASC(), f2.Title.ASC()).
 		LIMIT(1000)
 
-	queryStr, args, err := query.Sql()
-
-	assert.NilError(t, err)
-	assert.Equal(t, len(args), 1)
-	fmt.Println(queryStr)
+	assertQuery(t, query, expectedSql, int64(1000))
 
+	type thesameLengthFilms struct {
+		Title1 string
+		Title2 string
+		Length int16
+	}
 	films := []thesameLengthFilms{}
 
-	err = query.Query(db, &films)
+	err := query.Query(db, &films)
 
 	assert.NilError(t, err)
 
@@ -401,24 +535,41 @@ type staff struct {
 
 func TestSelectSelfReferenceType(t *testing.T) {
 
+	expectedSql := `
+SELECT DISTINCT staff.staff_id AS "staff.staff_id",
+     staff.first_name AS "staff.first_name",
+     staff.last_name AS "staff.last_name",
+     address.address_id AS "address.address_id",
+     address.address AS "address.address",
+     address.address2 AS "address.address2",
+     address.district AS "address.district",
+     address.city_id AS "address.city_id",
+     address.postal_code AS "address.postal_code",
+     address.phone AS "address.phone",
+     address.last_update AS "address.last_update",
+     manager.staff_id AS "manager.staff_id",
+     manager.first_name AS "manager.first_name"
+FROM dvds.staff
+     JOIN dvds.address ON staff.address_id = address.address_id
+     JOIN dvds.staff AS manager ON staff.staff_id = manager.staff_id;
+`
 	manager := Staff.AS("manager")
 
 	query := Staff.
 		INNER_JOIN(Address, Staff.AddressID.Eq(Address.AddressID)).
 		INNER_JOIN(manager, Staff.StaffID.Eq(manager.StaffID)).
-		SELECT(Staff.StaffID, Staff.FirstName, Staff.LastName, Address.AllColumns, manager.StaffID, manager.FirstName)
+		SELECT(Staff.StaffID, Staff.FirstName, Staff.LastName, Address.AllColumns, manager.StaffID, manager.FirstName).
+		DISTINCT()
 
-	queryStr, args, err := query.Sql()
-	assert.NilError(t, err)
-	fmt.Println(queryStr)
-	assert.Equal(t, len(args), 0)
+	assertQuery(t, query, expectedSql)
 
 	staffs := []staff{}
 
-	err = query.Query(db, &staffs)
+	err := query.Query(db, &staffs)
 
 	assert.NilError(t, err)
 
+	fmt.Println(query.DebugSql())
 	//spew.Dump(staffs)
 }
 
@@ -437,13 +588,34 @@ func TestSubQuery(t *testing.T) {
 	//
 	//fmt.Println(queryStr)
 	//
-	//avrgCustomer := sqlbuilder.NumExp(Customer.SELECT(Customer.LastName).LIMIT(1))
+	//avrgCustomer := NumExp(Customer.SELECT(Customer.LastName).LIMIT(1))
 	//
 	//Customer.
 	//	INNER_JOIN(selectStmtTable, Customer.LastName.Eq(selectStmtTable.RefStringColumn(Actor.FirstName))).
 	//	SELECT(Customer.AllColumns, selectStmtTable.RefIntColumnName("first_name")).
 	//	WHERE(Actor.LastName.Neq(avrgCustomer))
 
+	expectedQuery := `
+SELECT actor.actor_id AS "actor.actor_id",
+     actor.first_name AS "actor.first_name",
+     actor.last_name AS "actor.last_name",
+     actor.last_update AS "actor.last_update",
+     film_actor.actor_id AS "film_actor.actor_id",
+     film_actor.film_id AS "film_actor.film_id",
+     film_actor.last_update AS "film_actor.last_update",
+     films."film.title" AS "film.title",
+     films."film.rating" AS "film.rating"
+FROM dvds.actor
+     JOIN dvds.film_actor ON actor.actor_id = film_actor.film_id
+     JOIN (
+          SELECT film.film_id AS "film.film_id",
+               film.title AS "film.title",
+               film.rating AS "film.rating"
+          FROM dvds.film
+          WHERE film.rating = 'R'
+     ) AS films ON film_actor.film_id = films."film.film_id";
+`
+
 	rFilmsOnly := Film.SELECT(Film.FilmID, Film.Title, Film.Rating).
 		WHERE(Film.Rating.EqString("R")).
 		AsTable("films")
@@ -457,42 +629,70 @@ func TestSubQuery(t *testing.T) {
 			rFilmsOnly.RefStringColumn(Film.Rating).AS("film.rating"),
 		)
 
-	queryStr, args, err := query.Sql()
+	fmt.Println(query.Sql())
+
+	assertQuery(t, query, expectedQuery, "R")
+
+	dest := []model.Actor{}
+
+	err := query.Query(db, &dest)
 
 	assert.NilError(t, err)
-	assert.Equal(t, len(args), 1)
-	fmt.Println(queryStr)
-
 }
 
 func TestSelectFunctions(t *testing.T) {
-	query := Film.SELECT(sqlbuilder.MAX(Film.RentalRate).AS("max_film_rate"))
+	expectedQuery := `
+SELECT MAX(film.rental_rate) AS "max_film_rate"
+FROM dvds.film;
+`
+	query := Film.SELECT(MAX(Film.RentalRate).AS("max_film_rate"))
 
-	str, args, err := query.Sql()
+	assertQuery(t, query, expectedQuery)
+
+	ret := struct {
+		MaxFilmRate float64
+	}{}
+
+	err := query.Query(db, &ret)
 
 	assert.NilError(t, err)
-
-	assert.Equal(t, str, `SELECT MAX(film.rental_rate) AS "max_film_rate" FROM dvds.film`)
-	assert.Equal(t, len(args), 0)
-	fmt.Println(str)
+	assert.Equal(t, ret.MaxFilmRate, 4.99)
 }
 
 func TestSelectQueryScalar(t *testing.T) {
+	expectedSql := `
+SELECT film.film_id AS "film.film_id",
+     film.title AS "film.title",
+     film.description AS "film.description",
+     film.release_year AS "film.release_year",
+     film.language_id AS "film.language_id",
+     film.rental_duration AS "film.rental_duration",
+     film.rental_rate AS "film.rental_rate",
+     film.length AS "film.length",
+     film.replacement_cost AS "film.replacement_cost",
+     film.rating AS "film.rating",
+     film.last_update AS "film.last_update",
+     film.special_features AS "film.special_features",
+     film.fulltext AS "film.fulltext"
+FROM dvds.film
+WHERE film.rental_rate = (
+          SELECT MAX(film.rental_rate)
+          FROM dvds.film
+     )
+ORDER BY film.film_id ASC;
+`
 
-	maxFilmRentalRate := sqlbuilder.NumExp(Film.SELECT(sqlbuilder.MAX(Film.RentalRate)))
+	maxFilmRentalRate := NumExp(Film.SELECT(MAX(Film.RentalRate)))
 
 	query := Film.SELECT(Film.AllColumns).
 		WHERE(Film.RentalRate.Eq(maxFilmRentalRate)).
 		ORDER_BY(Film.FilmID.ASC())
 
-	queryStr, args, err := query.Sql()
-
-	assert.NilError(t, err)
-	assert.Equal(t, len(args), 0)
-	fmt.Println(queryStr)
+	fmt.Println(query.Sql())
+	assertQuery(t, query, expectedSql)
 
 	maxRentalRateFilms := []model.Film{}
-	err = query.Query(db, &maxRentalRateFilms)
+	err := query.Query(db, &maxRentalRateFilms)
 
 	assert.NilError(t, err)
 
@@ -515,26 +715,27 @@ func TestSelectQueryScalar(t *testing.T) {
 		SpecialFeatures: stringPtr("{Trailers,\"Deleted Scenes\"}"),
 		Fulltext:        "'ace':1 'administr':9 'ancient':19 'astound':4 'car':17 'china':20 'databas':8 'epistl':5 'explor':12 'find':15 'goldfing':2 'must':14",
 	})
-
-	//spew.Dump(maxRentalRateFilms[0])
 }
 
 func TestSelectGroupByHaving(t *testing.T) {
+	expectedSql := `
+SELECT payment.customer_id AS "customer_payment_sum.customer_id",
+     SUM(payment.amount) AS "customer_payment_sum.amount_sum"
+FROM dvds.payment
+GROUP BY payment.customer_id
+HAVING SUM(payment.amount) > 100
+ORDER BY SUM(payment.amount) ASC;
+`
 	customersPaymentQuery := Payment.
 		SELECT(
 			Payment.CustomerID.AS("customer_payment_sum.customer_id"),
-			sqlbuilder.SUM(Payment.Amount).AS("customer_payment_sum.amount_sum"),
+			SUM(Payment.Amount).AS("customer_payment_sum.amount_sum"),
 		).
 		GROUP_BY(Payment.CustomerID).
-		ORDER_BY(sqlbuilder.SUM(Payment.Amount).ASC()).
-		HAVING(sqlbuilder.SUM(Payment.Amount).Gt(sqlbuilder.NewNumericLiteral(100)))
+		ORDER_BY(SUM(Payment.Amount).ASC()).
+		HAVING(SUM(Payment.Amount).Gt(NewNumericLiteral(100)))
 
-	queryStr, args, err := customersPaymentQuery.Sql()
-
-	assert.NilError(t, err)
-	fmt.Println(queryStr)
-	assert.Equal(t, len(args), 1)
-	assert.Equal(t, queryStr, `SELECT payment.customer_id AS "customer_payment_sum.customer_id", SUM(payment.amount) AS "customer_payment_sum.amount_sum" FROM dvds.payment GROUP BY payment.customer_id HAVING SUM(payment.amount) > $1 ORDER BY SUM(payment.amount) ASC`)
+	assertQuery(t, customersPaymentQuery, expectedSql, 100)
 
 	type CustomerPaymentSum struct {
 		CustomerID int16
@@ -543,7 +744,7 @@ func TestSelectGroupByHaving(t *testing.T) {
 
 	customerPaymentSum := []CustomerPaymentSum{}
 
-	err = customersPaymentQuery.Query(db, &customerPaymentSum)
+	err := customersPaymentQuery.Query(db, &customerPaymentSum)
 
 	assert.NilError(t, err)
 
@@ -555,16 +756,32 @@ func TestSelectGroupByHaving(t *testing.T) {
 }
 
 func TestSelectGroupBy2(t *testing.T) {
-	type CustomerWithAmounts struct {
-		Customer  *model.Customer
-		AmountSum float64
-	}
-	customersWithAmounts := []CustomerWithAmounts{}
+	expectedSql := `
+SELECT customer.customer_id AS "customer.customer_id",
+     customer.store_id AS "customer.store_id",
+     customer.first_name AS "customer.first_name",
+     customer.last_name AS "customer.last_name",
+     customer.email AS "customer.email",
+     customer.address_id AS "customer.address_id",
+     customer.activebool AS "customer.activebool",
+     customer.create_date AS "customer.create_date",
+     customer.last_update AS "customer.last_update",
+     customer.active AS "customer.active",
+     customer_payment_sum.amount_sum AS "customer_with_amounts.amount_sum"
+FROM dvds.customer
+     JOIN (
+          SELECT payment.customer_id AS "payment.customer_id",
+               SUM(payment.amount) AS "amount_sum"
+          FROM dvds.payment
+          GROUP BY payment.customer_id
+     ) AS customer_payment_sum ON customer.customer_id = customer_payment_sum."payment.customer_id"
+ORDER BY customer_payment_sum.amount_sum ASC;
+`
 
 	customersPaymentSubQuery := Payment.
 		SELECT(
 			Payment.CustomerID,
-			sqlbuilder.SUM(Payment.Amount).AS("amount_sum"),
+			SUM(Payment.Amount).AS("amount_sum"),
 		).
 		GROUP_BY(Payment.CustomerID)
 
@@ -576,15 +793,16 @@ func TestSelectGroupBy2(t *testing.T) {
 		SELECT(Customer.AllColumns, amountSumColumn.AS("customer_with_amounts.amount_sum")).
 		ORDER_BY(amountSumColumn.ASC())
 
-	queryStr, args, err := query.Sql()
-	assert.NilError(t, err)
-	fmt.Println(queryStr)
-	assert.Equal(t, len(args), 0)
+	assertQuery(t, query, expectedSql)
 
-	err = query.Query(db, &customersWithAmounts)
-	assert.NilError(t, err)
-	//spew.Dump(customersWithAmounts)
+	type CustomerWithAmounts struct {
+		Customer  *model.Customer
+		AmountSum float64
+	}
+	customersWithAmounts := []CustomerWithAmounts{}
 
+	err := query.Query(db, &customersWithAmounts)
+	assert.NilError(t, err)
 	assert.Equal(t, len(customersWithAmounts), 599)
 
 	assert.DeepEqual(t, customersWithAmounts[0].Customer, &model.Customer{
@@ -603,19 +821,28 @@ func TestSelectGroupBy2(t *testing.T) {
 }
 
 func TestSelectTimeColumns(t *testing.T) {
+
+	expectedSql := `
+SELECT payment.payment_id AS "payment.payment_id",
+     payment.customer_id AS "payment.customer_id",
+     payment.staff_id AS "payment.staff_id",
+     payment.rental_id AS "payment.rental_id",
+     payment.amount AS "payment.amount",
+     payment.payment_date AS "payment.payment_date"
+FROM dvds.payment
+WHERE payment.payment_date <= '2007-02-14 22:16:01'
+ORDER BY payment.payment_date ASC;
+`
+
 	query := Payment.SELECT(Payment.AllColumns).
 		WHERE(Payment.PaymentDate.LtEqL("2007-02-14 22:16:01")).
 		ORDER_BY(Payment.PaymentDate.ASC())
 
-	queryStr, args, err := query.Sql()
-
-	assert.NilError(t, err)
-	assert.Equal(t, len(args), 1)
-	fmt.Println(queryStr)
+	assertQuery(t, query, expectedSql, "2007-02-14 22:16:01")
 
 	payments := []model.Payment{}
 
-	err = query.Query(db, &payments)
+	err := query.Query(db, &payments)
 
 	assert.NilError(t, err)
 
@@ -630,7 +857,27 @@ func TestSelectTimeColumns(t *testing.T) {
 }
 
 func TestUnion(t *testing.T) {
-	query := sqlbuilder.UNION(
+	expectedQuery := `
+(
+     (
+          SELECT payment.payment_id AS "payment.payment_id",
+               payment.amount AS "payment.amount"
+          FROM dvds.payment
+          WHERE payment.amount <= 100
+     )
+     UNION ALL
+     (
+          SELECT payment.payment_id AS "payment.payment_id",
+               payment.amount AS "payment.amount"
+          FROM dvds.payment
+          WHERE payment.amount >= 200
+     )
+)
+ORDER BY "payment.payment_id" ASC, "payment.amount" DESC
+LIMIT 10
+OFFSET 20;
+`
+	query := UNION_ALL(
 		Payment.
 			SELECT(Payment.PaymentID.AS("payment.payment_id"), Payment.Amount).
 			WHERE(Payment.Amount.LtEqL(100)),
@@ -638,19 +885,18 @@ func TestUnion(t *testing.T) {
 			SELECT(Payment.PaymentID, Payment.Amount).
 			WHERE(Payment.Amount.GtEqL(200)),
 	).
-		ORDER_BY(sqlbuilder.RefColumn("payment.payment_id").ASC(), Payment.Amount.DESC()).
-		LIMIT(10).OFFSET(20)
+		ORDER_BY(RefColumn("payment.payment_id").ASC(), Payment.Amount.DESC()).
+		LIMIT(10).
+		OFFSET(20)
 
-	queryStr, args, err := query.Sql()
+	queryStr, _, _ := query.Sql()
 
-	assert.NilError(t, err)
-
-	fmt.Println(queryStr)
-	fmt.Println(args)
+	fmt.Println("-" + queryStr + "-")
+	assertQuery(t, query, expectedQuery, int(100), int(200), int64(10), int64(20))
 
 	dest := []model.Payment{}
 
-	err = query.Query(db, &dest)
+	err := query.Query(db, &dest)
 
 	assert.NilError(t, err)
 	assert.Equal(t, len(dest), 10)
@@ -669,26 +915,29 @@ func TestUnion(t *testing.T) {
 }
 
 func TestSelectWithCase(t *testing.T) {
+	expectedQuery := `
+SELECT (CASE payment.staff_id WHEN 1 THEN 'ONE' WHEN 2 THEN 'TWO' WHEN 3 THEN 'THREE' ELSE 'OTHER' END) AS "staff_id_num"
+FROM dvds.payment
+ORDER BY payment.payment_id ASC
+LIMIT 20;
+`
 	query := Payment.SELECT(
-		sqlbuilder.CASE(Payment.StaffID).
-			WHEN(sqlbuilder.IntLiteral(1)).THEN(sqlbuilder.Literal("ONE")).
-			WHEN(sqlbuilder.IntLiteral(2)).THEN(sqlbuilder.Literal("TWO")).
-			WHEN(sqlbuilder.IntLiteral(3)).THEN(sqlbuilder.Literal("THREE")).
-			ELSE(sqlbuilder.Literal("OTHER")).AS("staff_id_num"),
+		CASE(Payment.StaffID).
+			WHEN(IntLiteral(1)).THEN(Literal("ONE")).
+			WHEN(IntLiteral(2)).THEN(Literal("TWO")).
+			WHEN(IntLiteral(3)).THEN(Literal("THREE")).
+			ELSE(Literal("OTHER")).AS("staff_id_num"),
 	).
 		ORDER_BY(Payment.PaymentID.ASC()).
 		LIMIT(20)
 
-	queryStr, _, err := query.Sql()
-
-	assert.NilError(t, err)
-	assert.Equal(t, queryStr, `SELECT (CASE payment.staff_id WHEN $1 THEN $2 WHEN $3 THEN $4 WHEN $5 THEN $6 ELSE $7 END) AS "staff_id_num" FROM dvds.payment ORDER BY payment.payment_id ASC LIMIT $8`)
+	assertQuery(t, query, expectedQuery, 1, "ONE", 2, "TWO", 3, "THREE", "OTHER", int64(20))
 
 	dest := []struct {
 		StaffIdNum string
 	}{}
 
-	err = query.Query(db, &dest)
+	err := query.Query(db, &dest)
 
 	assert.NilError(t, err)
 	assert.Equal(t, len(dest), 20)
@@ -697,84 +946,19 @@ func TestSelectWithCase(t *testing.T) {
 }
 
 func TestLockTable(t *testing.T) {
-	query := Address.LOCK().IN(sqlbuilder.LOCK_EXCLUSIVE).NOWAIT()
+	expectedSql := `
+LOCK TABLE dvds.address IN EXCLUSIVE MODE NOWAIT;
+`
+	query := Address.LOCK().IN(LOCK_EXCLUSIVE).NOWAIT()
 
-	queryStr, _, err := query.Sql()
+	querySql, _, _ := query.Sql()
+	fmt.Println("-" + querySql + "-")
 
-	assert.NilError(t, err)
-	assert.Equal(t, queryStr, `LOCK TABLE dvds.address IN EXCLUSIVE MODE NOWAIT`)
+	assertQuery(t, query, expectedSql)
 
 	tx, _ := db.Begin()
 
-	_, err = query.Execute(tx)
+	_, err := query.Execute(tx)
 
 	assert.NilError(t, err)
 }
-
-func int16Ptr(i int16) *int16 {
-	return &i
-}
-
-func int32Ptr(i int32) *int32 {
-	return &i
-}
-
-func stringPtr(s string) *string {
-	return &s
-}
-
-func timeWithoutTimeZone(t string, precision int) *time.Time {
-
-	precisionStr := ""
-
-	if precision > 0 {
-		precisionStr = "." + strings.Repeat("9", precision)
-	}
-
-	time, err := time.Parse("2006-01-02 15:04:05"+precisionStr+" +0000", t+" +0000")
-
-	if err != nil {
-		panic(err)
-	}
-
-	return &time
-}
-
-var customer0 = model.Customer{
-	CustomerID: 1,
-	StoreID:    1,
-	FirstName:  "Mary",
-	LastName:   "Smith",
-	Email:      stringPtr("mary.smith@sakilacustomer.org"),
-	Address:    nil,
-	Activebool: true,
-	CreateDate: *timeWithoutTimeZone("2006-02-14 00:00:00", 0),
-	LastUpdate: timeWithoutTimeZone("2013-05-26 14:49:45.738", 3),
-	Active:     int32Ptr(1),
-}
-
-var customer1 = model.Customer{
-	CustomerID: 2,
-	StoreID:    1,
-	FirstName:  "Patricia",
-	LastName:   "Johnson",
-	Email:      stringPtr("patricia.johnson@sakilacustomer.org"),
-	Address:    nil,
-	Activebool: true,
-	CreateDate: *timeWithoutTimeZone("2006-02-14 00:00:00", 0),
-	LastUpdate: timeWithoutTimeZone("2013-05-26 14:49:45.738", 3),
-	Active:     int32Ptr(1),
-}
-
-var lastCustomer = model.Customer{
-	CustomerID: 599,
-	StoreID:    2,
-	FirstName:  "Austin",
-	LastName:   "Cintron",
-	Email:      stringPtr("austin.cintron@sakilacustomer.org"),
-	Address:    nil,
-	Activebool: true,
-	CreateDate: *timeWithoutTimeZone("2006-02-14 00:00:00", 0),
-	LastUpdate: timeWithoutTimeZone("2013-05-26 14:49:45.738", 3),
-	Active:     int32Ptr(1),
-}
diff --git a/tests/test_util.go b/tests/test_util.go
new file mode 100644
index 0000000..2c445ec
--- /dev/null
+++ b/tests/test_util.go
@@ -0,0 +1,89 @@
+package tests
+
+import (
+	"github.com/sub0zero/go-sqlbuilder/sqlbuilder"
+	"github.com/sub0zero/go-sqlbuilder/tests/.test_files/dvd_rental/dvds/model"
+	"gotest.tools/assert"
+	"strings"
+	"testing"
+	"time"
+)
+
+func assertQuery(t *testing.T, query sqlbuilder.Statement, expectedQuery string, expectedArgs ...interface{}) {
+	_, args, err := query.Sql()
+	assert.NilError(t, err)
+	//assert.Equal(t, queryStr, expectedQuery)
+	assert.DeepEqual(t, args, expectedArgs)
+
+	debuqSql, err := query.DebugSql()
+	assert.NilError(t, err)
+	assert.Equal(t, debuqSql, expectedQuery, args)
+}
+
+func int16Ptr(i int16) *int16 {
+	return &i
+}
+
+func int32Ptr(i int32) *int32 {
+	return &i
+}
+
+func stringPtr(s string) *string {
+	return &s
+}
+
+func timeWithoutTimeZone(t string, precision int) *time.Time {
+
+	precisionStr := ""
+
+	if precision > 0 {
+		precisionStr = "." + strings.Repeat("9", precision)
+	}
+
+	time, err := time.Parse("2006-01-02 15:04:05"+precisionStr+" +0000", t+" +0000")
+
+	if err != nil {
+		panic(err)
+	}
+
+	return &time
+}
+
+var customer0 = model.Customer{
+	CustomerID: 1,
+	StoreID:    1,
+	FirstName:  "Mary",
+	LastName:   "Smith",
+	Email:      stringPtr("mary.smith@sakilacustomer.org"),
+	Address:    nil,
+	Activebool: true,
+	CreateDate: *timeWithoutTimeZone("2006-02-14 00:00:00", 0),
+	LastUpdate: timeWithoutTimeZone("2013-05-26 14:49:45.738", 3),
+	Active:     int32Ptr(1),
+}
+
+var customer1 = model.Customer{
+	CustomerID: 2,
+	StoreID:    1,
+	FirstName:  "Patricia",
+	LastName:   "Johnson",
+	Email:      stringPtr("patricia.johnson@sakilacustomer.org"),
+	Address:    nil,
+	Activebool: true,
+	CreateDate: *timeWithoutTimeZone("2006-02-14 00:00:00", 0),
+	LastUpdate: timeWithoutTimeZone("2013-05-26 14:49:45.738", 3),
+	Active:     int32Ptr(1),
+}
+
+var lastCustomer = model.Customer{
+	CustomerID: 599,
+	StoreID:    2,
+	FirstName:  "Austin",
+	LastName:   "Cintron",
+	Email:      stringPtr("austin.cintron@sakilacustomer.org"),
+	Address:    nil,
+	Activebool: true,
+	CreateDate: *timeWithoutTimeZone("2006-02-14 00:00:00", 0),
+	LastUpdate: timeWithoutTimeZone("2013-05-26 14:49:45.738", 3),
+	Active:     int32Ptr(1),
+}