init - add project files

tools/jet-2.12.0/postgres/set_statement.go

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+package postgres
+
+import "github.com/go-jet/jet/v2/internal/jet"
+
+// UNION effectively appends the result of sub-queries(select statements) into single query.
+// It eliminates duplicate rows from its result.
+func UNION(lhs, rhs jet.SerializerStatement, selects ...jet.SerializerStatement) setStatement {
+	return newSetStatementImpl(union, false, toSelectList(lhs, rhs, selects...))
+}
+
+// UNION_ALL effectively appends the result of sub-queries(select statements) into single query.
+// It does not eliminates duplicate rows from its result.
+func UNION_ALL(lhs, rhs jet.SerializerStatement, selects ...jet.SerializerStatement) setStatement {
+	return newSetStatementImpl(union, true, toSelectList(lhs, rhs, selects...))
+}
+
+// INTERSECT returns all rows that are in query results.
+// It eliminates duplicate rows from its result.
+func INTERSECT(lhs, rhs jet.SerializerStatement, selects ...jet.SerializerStatement) setStatement {
+	return newSetStatementImpl(intersect, false, toSelectList(lhs, rhs, selects...))
+}
+
+// INTERSECT_ALL returns all rows that are in query results.
+// It does not eliminates duplicate rows from its result.
+func INTERSECT_ALL(lhs, rhs jet.SerializerStatement, selects ...jet.SerializerStatement) setStatement {
+	return newSetStatementImpl(intersect, true, toSelectList(lhs, rhs, selects...))
+}
+
+// EXCEPT returns all rows that are in the result of query lhs but not in the result of query rhs.
+// It eliminates duplicate rows from its result.
+func EXCEPT(lhs, rhs jet.SerializerStatement) setStatement {
+	return newSetStatementImpl(except, false, toSelectList(lhs, rhs))
+}
+
+// EXCEPT_ALL returns all rows that are in the result of query lhs but not in the result of query rhs.
+// It does not eliminates duplicate rows from its result.
+func EXCEPT_ALL(lhs, rhs jet.SerializerStatement) setStatement {
+	return newSetStatementImpl(except, true, toSelectList(lhs, rhs))
+}
+
+type setStatement interface {
+	setOperators
+
+	ORDER_BY(orderByClauses ...OrderByClause) setStatement
+
+	LIMIT(limit int64) setStatement
+	OFFSET(offset int64) setStatement
+	// OFFSET_e can be used when an integer expression is needed as offset, otherwise OFFSET can be used
+	OFFSET_e(offset IntegerExpression) setStatement
+
+	AsTable(alias string) SelectTable
+}
+
+type setOperators interface {
+	Statement
+	jet.HasProjections
+	Expression
+
+	UNION(rhs SelectStatement) setStatement
+	UNION_ALL(rhs SelectStatement) setStatement
+	INTERSECT(rhs SelectStatement) setStatement
+	INTERSECT_ALL(rhs SelectStatement) setStatement
+	EXCEPT(rhs SelectStatement) setStatement
+	EXCEPT_ALL(rhs SelectStatement) setStatement
+}
+
+type setOperatorsImpl struct {
+	parent setOperators
+}
+
+func (s *setOperatorsImpl) UNION(rhs SelectStatement) setStatement {
+	return UNION(s.parent, rhs)
+}
+
+func (s *setOperatorsImpl) UNION_ALL(rhs SelectStatement) setStatement {
+	return UNION_ALL(s.parent, rhs)
+}
+
+func (s *setOperatorsImpl) INTERSECT(rhs SelectStatement) setStatement {
+	return INTERSECT(s.parent, rhs)
+}
+
+func (s *setOperatorsImpl) INTERSECT_ALL(rhs SelectStatement) setStatement {
+	return INTERSECT_ALL(s.parent, rhs)
+}
+
+func (s *setOperatorsImpl) EXCEPT(rhs SelectStatement) setStatement {
+	return EXCEPT(s.parent, rhs)
+}
+
+func (s *setOperatorsImpl) EXCEPT_ALL(rhs SelectStatement) setStatement {
+	return EXCEPT_ALL(s.parent, rhs)
+}
+
+type setStatementImpl struct {
+	jet.ExpressionStatement
+
+	setOperatorsImpl
+
+	setOperator jet.ClauseSetStmtOperator
+}
+
+func newSetStatementImpl(operator string, all bool, selects []jet.SerializerStatement) setStatement {
+	newSetStatement := &setStatementImpl{}
+	newSetStatement.ExpressionStatement = jet.NewExpressionStatementImpl(Dialect, jet.SetStatementType, newSetStatement,
+		&newSetStatement.setOperator)
+
+	newSetStatement.setOperator.Operator = operator
+	newSetStatement.setOperator.All = all
+	newSetStatement.setOperator.Selects = selects
+	newSetStatement.setOperator.Limit.Count = -1
+
+	newSetStatement.setOperatorsImpl.parent = newSetStatement
+
+	return newSetStatement
+}
+
+func (s *setStatementImpl) ORDER_BY(orderByClauses ...OrderByClause) setStatement {
+	s.setOperator.OrderBy.List = orderByClauses
+	return s
+}
+
+func (s *setStatementImpl) LIMIT(limit int64) setStatement {
+	s.setOperator.Limit.Count = limit
+	return s
+}
+
+func (s *setStatementImpl) OFFSET(offset int64) setStatement {
+	s.setOperator.Offset.Count = Int(offset)
+	return s
+}
+
+func (s *setStatementImpl) OFFSET_e(offset IntegerExpression) setStatement {
+	s.setOperator.Offset.Count = offset
+	return s
+}
+
+func (s *setStatementImpl) AsTable(alias string) SelectTable {
+	return newSelectTable(s, alias, nil)
+}
+
+const (
+	union     = "UNION"
+	intersect = "INTERSECT"
+	except    = "EXCEPT"
+)
+
+func toSelectList(lhs, rhs jet.SerializerStatement, selects ...jet.SerializerStatement) []jet.SerializerStatement {
+	return append([]jet.SerializerStatement{lhs, rhs}, selects...)
+}