Functions go doc.

internal/jet/clause.go

@@ -11,7 +11,7 @@ type Clause interface {
 type ClauseWithProjections interface {
 	Clause
 
-	projections() []Projection
+	projections() ProjectionList
 }
 
 type ClauseSelect struct {
@@ -19,7 +19,7 @@ type ClauseSelect struct {
 	Projections []Projection
 }
 
-func (s *ClauseSelect) projections() []Projection {
+func (s *ClauseSelect) projections() ProjectionList {
 	return s.Projections
 }
 
@@ -172,7 +172,7 @@ type ClauseSetStmtOperator struct {
 	Offset   ClauseOffset
 }
 
-func (s *ClauseSetStmtOperator) projections() []Projection {
+func (s *ClauseSetStmtOperator) projections() ProjectionList {
 	if len(s.Selects) > 0 {
 		return s.Selects[0].projections()
 	}

internal/jet/func_expression.go

@@ -17,10 +17,12 @@ func ABSi(integerExpression IntegerExpression) IntegerExpression {
 	return newIntegerFunc("ABS", integerExpression)
 }
 
+// POW calculates power of base with exponent
 func POW(base, exponent NumericExpression) FloatExpression {
 	return NewFloatFunc("POW", base, exponent)
 }
 
+// POWER calculates power of base with exponent
 func POWER(base, exponent NumericExpression) FloatExpression {
 	return NewFloatFunc("POWER", base, exponent)
 }
@@ -202,12 +204,14 @@ func CHR(integerExpression IntegerExpression) StringExpression {
 	return newStringFunc("CHR", integerExpression)
 }
 
+// CONCAT adds two or more expressions together
 func CONCAT(expressions ...Expression) StringExpression {
 	return newStringFunc("CONCAT", expressions...)
 }
 
-func CONCAT_WS(expressions ...Expression) StringExpression {
-	return newStringFunc("CONCAT_WS", expressions...)
+// CONCAT_WS adds two or more expressions together with a separator.
+func CONCAT_WS(separator Expression, expressions ...Expression) StringExpression {
+	return newStringFunc("CONCAT_WS", append([]Expression{separator}, expressions...)...)
 }
 
 // CONVERT converts string to dest_encoding. The original encoding is
@@ -240,6 +244,7 @@ func DECODE(data StringExpression, format StringExpression) StringExpression {
 	return newStringFunc("DECODE", data, format)
 }
 
+// FORMAT formats a number to a format like "#,###,###.##", rounded to a specified number of decimal places, then it returns the result as a string.
 func FORMAT(formatStr StringExpression, formatArgs ...Expression) StringExpression {
 	args := []Expression{formatStr}
 	args = append(args, formatArgs...)
@@ -341,6 +346,7 @@ func TO_HEX(number IntegerExpression) StringExpression {
 	return newStringFunc("TO_HEX", number)
 }
 
+// REGEXP_LIKE Returns 1 if the string expr matches the regular expression specified by the pattern pat, 0 otherwise.
 func REGEXP_LIKE(stringExp StringExpression, pattern StringExpression, matchType ...string) BoolExpression {
 	if len(matchType) > 0 {
 		return newBoolFunc("REGEXP_LIKE", stringExp, pattern, String(matchType[0], true))

internal/jet/select_table.go

@@ -10,17 +10,14 @@ type SelectTableImpl struct {
 	selectStmt StatementWithProjections
 	alias      string
 
-	projections []Projection
+	projections ProjectionList
 }
 
 func NewSelectTable(selectStmt StatementWithProjections, alias string) SelectTableImpl {
 	selectTable := SelectTableImpl{selectStmt: selectStmt, alias: alias}
 
-	for _, projection := range selectStmt.projections() {
-		newProjection := projection.fromImpl(&selectTable)
-
-		selectTable.projections = append(selectTable.projections, newProjection)
-	}
+	projectionList := selectStmt.projections().fromImpl(&selectTable)
+	selectTable.projections = projectionList.(ProjectionList)
 
 	return selectTable
 }

internal/jet/statement.go

@@ -39,7 +39,7 @@ type StatementWithProjections interface {
 }
 
 type HasProjections interface {
-	projections() []Projection
+	projections() ProjectionList
 }
 
 type SerializerStatementInterfaceImpl struct {
@@ -116,7 +116,7 @@ type StatementImpl struct {
 	Clauses []Clause
 }
 
-func (s *StatementImpl) projections() []Projection {
+func (s *StatementImpl) projections() ProjectionList {
 	for _, clause := range s.Clauses {
 		if selectClause, ok := clause.(ClauseWithProjections); ok {
 			return selectClause.projections()