jet/sqlbuilder/order_by_clause.go
2019-05-07 19:06:21 +02:00

46 lines
848 B
Go

package sqlbuilder
import "github.com/dropbox/godropbox/errors"
type orderByClause interface {
clause
isOrderByClauseType()
}
type isOrderByClause struct {
}
func (o *isOrderByClause) isOrderByClauseType() {
}
type orderByClauseImpl struct {
isOrderByClause
expression expression
ascent bool
}
func (o *orderByClauseImpl) serialize(out *queryData) error {
if o.expression == nil {
return errors.Newf("nil orderBy by clause.")
}
if err := o.expression.serialize(out); err != nil {
return err
}
if o.ascent {
out.WriteString(" ASC")
} else {
out.WriteString(" DESC")
}
return nil
}
func ASC(expression expression) orderByClause {
return &orderByClauseImpl{expression: expression, ascent: true}
}
func DESC(expression expression) orderByClause {
return &orderByClauseImpl{expression: expression, ascent: false}
}