} else {
		builder.WriteQuoted(insert.Table)
	}
}

// MergeClause merge insert clause
func (insert Insert) MergeClause(clause *Clause) {
	if v, ok := clause.Expression.(Insert); ok {
		if insert.Modifier == "" {
			insert.Modifier = v.Modifier
		}
		if insert.Table.Name == "" {
			insert.Table = v.Table
		}
	}
	clause.Expression = insert

		},
		{
			[]clause.Interface{clause.Select{}, clause.From{}, clause.Limit{Limit: &limit0}},
			"SELECT * FROM `users` LIMIT ?",
			[]interface{}{limit0},
		},
		{
			[]clause.Interface{clause.Select{}, clause.From{}, clause.Limit{Limit: &limit0}, clause.Limit{Offset: 0}},
			"SELECT * FROM `users` LIMIT ?",
			[]interface{}{limit0},
		},
		{
			[]clause.Interface{clause.Select{}, clause.From{}, clause.Limit{Offset: 20}},

			}
		}
	}
}

// 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))

				},
			},
			sql: "LEFT JOIN `user` ON `user_info`.`user_id` = `users`.`id`",
		},
		{
			name: "RIGHT JOIN",
			join: clause.Join{
				Type:  clause.RightJoin,
				Table: clause.Table{Name: "user"},
				ON: clause.Where{
					Exprs: []clause.Expression{clause.Eq{clause.Column{Table: "user_info", Name: "user_id"}, clause.PrimaryColumn}},
				},
			},

	}
}

// MergeClause merge order by clauses
func (returning Returning) MergeClause(clause *Clause) {
	if v, ok := clause.Expression.(Returning); ok {
		returning.Columns = append(v.Columns, returning.Columns...)
	}

	clause.Expression = returning

package clause_test

import (
	"fmt"
	"testing"

	"gorm.io/gorm/clause"
)

func TestValues(t *testing.T) {
	results := []struct {
		Clauses []clause.Interface
		Result  string
		Vars    []interface{}
	}{
		{
			[]clause.Interface{
				clause.Insert{},
				clause.Values{
					Columns: []clause.Column{{Name: "name"}, {Name: "age"}},
					Values:  [][]interface{}{{"jinzhu", 18}, {"josh", 1}},
				},
			},

package clause

// GroupBy group by clause
type GroupBy struct {
	Columns []Column
	Having  []Expression
}

// Name from clause name
func (groupBy GroupBy) Name() string {
	return "GROUP BY"
}

// Build build group by clause
func (groupBy GroupBy) Build(builder Builder) {
	for idx, column := range groupBy.Columns {
		if idx > 0 {
			builder.WriteByte(',')
		}

		builder.WriteQuoted(column)
	}

package clause_test

import (
	"fmt"
	"testing"

	"gorm.io/gorm/clause"
)

func TestDelete(t *testing.T) {
	results := []struct {
		Clauses []clause.Interface
		Result  string
		Vars    []interface{}
	}{
		{
			[]clause.Interface{clause.Delete{}, clause.From{}},
			"DELETE FROM `users`", nil,
		},
		{
			[]clause.Interface{clause.Delete{Modifier: "LOW_PRIORITY"}, clause.From{}},

		clauses := []clause.Interface{
			clause.Select{},
			clause.From{},
			clause.Where{Exprs: []clause.Expression{
				clause.Eq{Column: clause.PrimaryColumn, Value: "1"},
				clause.Gt{Column: "age", Value: 18},
				clause.Or(clause.Neq{Column: "name", Value: "jinzhu"}),
			}},
			clause.Where{Exprs: []clause.Expression{

		},
		{
			[]clause.Interface{clause.Select{
				Columns: []clause.Column{clause.PrimaryColumn},
			}, clause.Select{
				Columns: []clause.Column{{Name: "name"}},
			}, clause.From{}},
			"SELECT `name` FROM `users`", nil,
		},
		{
			[]clause.Interface{clause.Select{
				Expression: clause.CommaExpression{
					Exprs: []clause.Expression{
						clause.NamedExpr{"?", []interface{}{clause.Column{Name: "id"}}},