gorm/clause/order_by.go

55 lines
1.1 KiB
Go

package clause
type OrderByColumn struct {
Column Column
Desc bool
Reorder bool
}
type OrderBy struct {
Columns []OrderByColumn
Expression Expression
}
// Name where clause name
func (orderBy OrderBy) Name() string {
return "ORDER BY"
}
// Build build where clause
func (orderBy OrderBy) Build(builder Builder) {
if orderBy.Expression != nil {
orderBy.Expression.Build(builder)
} else {
for idx, column := range orderBy.Columns {
if idx > 0 {
builder.WriteByte(',')
}
builder.WriteQuoted(column.Column)
if column.Desc {
builder.WriteString(" DESC")
}
}
}
}
// MergeClause merge order by clauses
func (orderBy OrderBy) MergeClause(clause *Clause) {
if v, ok := clause.Expression.(OrderBy); ok {
for i := len(orderBy.Columns) - 1; i >= 0; i-- {
if orderBy.Columns[i].Reorder {
orderBy.Columns = orderBy.Columns[i:]
clause.Expression = orderBy
return
}
}
copiedColumns := make([]OrderByColumn, len(v.Columns))
copy(copiedColumns, v.Columns)
orderBy.Columns = append(copiedColumns, orderBy.Columns...)
}
clause.Expression = orderBy
}