Conditional expression functions.

This commit is contained in:
zer0sub 2019-06-03 17:38:47 +02:00
parent ca5a30983e
commit dca028295d
7 changed files with 89 additions and 15 deletions

View file

@ -503,3 +503,27 @@ func LOCALTIMESTAMP(precision ...int) TimestampExpression {
func NOW() TimestampzExpression {
return newTimestampzFunc("NOW")
}
// --------------- Conditional Expressions Functions -------------//
func COALESCE(value expression, values ...expression) expression {
var allValues = []expression{value}
allValues = append(allValues, values...)
return newFunc("COALESCE", allValues, nil)
}
func NULLIF(value1, value2 expression) expression {
return newFunc("NULLIF", []expression{value1, value2}, nil)
}
func GREATEST(value expression, values ...expression) expression {
var allValues = []expression{value}
allValues = append(allValues, values...)
return newFunc("GREATEST", allValues, nil)
}
func LEAST(value expression, values ...expression) expression {
var allValues = []expression{value}
allValues = append(allValues, values...)
return newFunc("LEAST", allValues, nil)
}

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@ -118,23 +118,24 @@ func TestFuncLOG(t *testing.T) {
assertExpressionSerialize(t, LOG(Float(11.2222)), "LOG($1)", float64(11.2222))
}
func TestCase1(t *testing.T) {
query := CASE().
WHEN(table3Col1.EQ(Int(1))).THEN(table3Col1.ADD(Int(1))).
WHEN(table3Col1.EQ(Int(2))).THEN(table3Col1.ADD(Int(2)))
assertExpressionSerialize(t, query, `(CASE WHEN table3.col1 = $1 THEN table3.col1 + $2 WHEN table3.col1 = $3 THEN table3.col1 + $4 END)`,
int64(1), int64(1), int64(2), int64(2))
func TestFuncCOALESCE(t *testing.T) {
assertExpressionSerialize(t, COALESCE(table1ColFloat), "COALESCE(table1.colFloat)")
assertExpressionSerialize(t, COALESCE(Float(11.2222), NULL, String("str")), "COALESCE($1, NULL, $2)", float64(11.2222), "str")
}
func TestCase2(t *testing.T) {
query := CASE(table3Col1).
WHEN(Int(1)).THEN(table3Col1.ADD(Int(1))).
WHEN(Int(2)).THEN(table3Col1.ADD(Int(2))).
ELSE(Int(0))
func TestFuncNULLIF(t *testing.T) {
assertExpressionSerialize(t, NULLIF(table1ColFloat, table2ColInt), "NULLIF(table1.colFloat, table2.colInt)")
assertExpressionSerialize(t, NULLIF(Float(11.2222), NULL), "NULLIF($1, NULL)", float64(11.2222))
}
assertExpressionSerialize(t, query, `(CASE table3.col1 WHEN $1 THEN table3.col1 + $2 WHEN $3 THEN table3.col1 + $4 ELSE $5 END)`,
int64(1), int64(1), int64(2), int64(2), int64(0))
func TestFuncGREATEST(t *testing.T) {
assertExpressionSerialize(t, GREATEST(table1ColFloat), "GREATEST(table1.colFloat)")
assertExpressionSerialize(t, GREATEST(Float(11.2222), NULL, String("str")), "GREATEST($1, NULL, $2)", float64(11.2222), "str")
}
func TestFuncLEAST(t *testing.T) {
assertExpressionSerialize(t, LEAST(table1ColFloat), "LEAST(table1.colFloat)")
assertExpressionSerialize(t, LEAST(Float(11.2222), NULL, String("str")), "LEAST($1, NULL, $2)", float64(11.2222), "str")
}
func TestInterval(t *testing.T) {

View file

@ -4,6 +4,10 @@ const (
DEFAULT keywordClause = "DEFAULT"
)
var (
NULL = newNullExpression()
)
type keywordClause string
func (k keywordClause) serialize(statement statementType, out *queryData, options ...serializeOption) error {

View file

@ -175,3 +175,21 @@ func Date(year, month, day int) DateExpression {
return dateLiteral.CAST_TO_DATE()
}
//--------------------------------------------------//
type nullExpression struct {
expressionInterfaceImpl
}
func newNullExpression() expression {
nullExpression := &nullExpression{}
nullExpression.expressionInterfaceImpl.parent = nullExpression
return nullExpression
}
func (n *nullExpression) serialize(statement statementType, out *queryData, options ...serializeOption) error {
out.writeString("NULL")
return nil
}

View file

@ -124,7 +124,7 @@ type caseOperatorImpl struct {
func CASE(expression ...expression) caseOperatorExpression {
caseExp := &caseOperatorImpl{}
if len(expression) == 1 {
if len(expression) > 0 {
caseExp.expression = expression[0]
}

View file

@ -0,0 +1,22 @@
package sqlbuilder
import "testing"
func TestCase1(t *testing.T) {
query := CASE().
WHEN(table3Col1.EQ(Int(1))).THEN(table3Col1.ADD(Int(1))).
WHEN(table3Col1.EQ(Int(2))).THEN(table3Col1.ADD(Int(2)))
assertExpressionSerialize(t, query, `(CASE WHEN table3.col1 = $1 THEN table3.col1 + $2 WHEN table3.col1 = $3 THEN table3.col1 + $4 END)`,
int64(1), int64(1), int64(2), int64(2))
}
func TestCase2(t *testing.T) {
query := CASE(table3Col1).
WHEN(Int(1)).THEN(table3Col1.ADD(Int(1))).
WHEN(Int(2)).THEN(table3Col1.ADD(Int(2))).
ELSE(Int(0))
assertExpressionSerialize(t, query, `(CASE table3.col1 WHEN $1 THEN table3.col1 + $2 WHEN $3 THEN table3.col1 + $4 ELSE $5 END)`,
int64(1), int64(1), int64(2), int64(2), int64(0))
}

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@ -48,6 +48,11 @@ func TestExpressionOperators(t *testing.T) {
TO_DATE(String("05 Dec 2000"), String("DD Mon YYYY")),
TO_NUMBER(String("12,454"), String("99G999D9S")),
TO_TIMESTAMP(String("05 Dec 2000"), String("DD Mon YYYY")),
COALESCE(AllTypes.IntegerPtr, AllTypes.SmallintPtr, NULL, Int(11)),
NULLIF(AllTypes.Text, String("(none)")),
GREATEST(AllTypes.Numeric, AllTypes.NumericPtr),
LEAST(AllTypes.Numeric, AllTypes.NumericPtr),
)
fmt.Println(query.DebugSql())