mirror of https://github.com/go-gorm/gorm.git
49 lines
999 B
Go
49 lines
999 B
Go
package clause
|
|
|
|
import "strconv"
|
|
|
|
// Limit limit clause
|
|
type Limit struct {
|
|
Limit *int
|
|
Offset int
|
|
}
|
|
|
|
// Name where clause name
|
|
func (limit Limit) Name() string {
|
|
return "LIMIT"
|
|
}
|
|
|
|
// Build build where clause
|
|
func (limit Limit) Build(builder Builder) {
|
|
if limit.Limit != nil && *limit.Limit >= 0 {
|
|
builder.WriteString("LIMIT ")
|
|
builder.WriteString(strconv.Itoa(*limit.Limit))
|
|
}
|
|
if limit.Offset > 0 {
|
|
if limit.Limit != nil && *limit.Limit >= 0 {
|
|
builder.WriteByte(' ')
|
|
}
|
|
builder.WriteString("OFFSET ")
|
|
builder.WriteString(strconv.Itoa(limit.Offset))
|
|
}
|
|
}
|
|
|
|
// MergeClause merge order by clauses
|
|
func (limit Limit) MergeClause(clause *Clause) {
|
|
clause.Name = ""
|
|
|
|
if v, ok := clause.Expression.(Limit); ok {
|
|
if (limit.Limit == nil || *limit.Limit == 0) && (v.Limit != nil && *v.Limit != 0) {
|
|
limit.Limit = v.Limit
|
|
}
|
|
|
|
if limit.Offset == 0 && v.Offset > 0 {
|
|
limit.Offset = v.Offset
|
|
} else if limit.Offset < 0 {
|
|
limit.Offset = 0
|
|
}
|
|
}
|
|
|
|
clause.Expression = limit
|
|
}
|