if w, ok := clause.Expression.(Where); ok {
		exprs := make([]Expression, len(w.Exprs)+len(where.Exprs))
		copy(exprs, w.Exprs)
		copy(exprs[len(w.Exprs):], where.Exprs)
		where.Exprs = exprs
	}

	clause.Expression = where
}

func And(exprs ...Expression) Expression {
	if len(exprs) == 0 {
		return nil
	}

	if len(exprs) == 1 {
		if _, ok := exprs[0].(OrConditions); !ok {
			return exprs[0]
		}

				Exprs: []clause.Expression{clause.Or(clause.Neq{Column: "name", Value: "jinzhu"}), clause.Eq{Column: clause.PrimaryColumn, Value: "1"}, clause.Gt{Column: "age", Value: 18}},
			}},
			"SELECT * FROM `users` WHERE `users`.`id` = ? OR `name` <> ? AND `age` > ?",
			[]interface{}{"1", "jinzhu", 18},
		},
		{
			[]clause.Interface{clause.Select{}, clause.From{}, clause.Where{

		}

		if len(onConflict.TargetWhere.Exprs) > 0 {
			builder.WriteString(" WHERE ")
			onConflict.TargetWhere.Build(builder)
			builder.WriteByte(' ')
		}
	}

	if onConflict.DoNothing {
		builder.WriteString("DO NOTHING")
	} else {
		builder.WriteString("DO UPDATE SET ")
		onConflict.DoUpdates.Build(builder)
	}

	if len(onConflict.Where.Exprs) > 0 {
		builder.WriteString(" WHERE ")

				for _, expr := range where.Exprs {
					if orCond, ok := expr.(clause.OrConditions); ok && len(orCond.Exprs) == 1 {
						where.Exprs = []clause.Expression{clause.And(where.Exprs...)}
						c.Expression = where
						stmt.Clauses["WHERE"] = c
						break
					}
				}
			}
		}

		stmt.AddClause(clause.Where{Exprs: []clause.Expression{

				ON: clause.Where{
					Exprs: []clause.Expression{clause.Eq{clause.Column{Table: "user_info", Name: "user_id"}, clause.PrimaryColumn}},
				},
			},
			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{

		}

		return tx.Create(dest)
	} else if len(db.Statement.assigns) > 0 {
		exprs := tx.Statement.BuildCondition(db.Statement.assigns[0], db.Statement.assigns[1:]...)
		assigns := map[string]interface{}{}
		for i := 0; i < len(exprs); i++ {
			expr := exprs[i]

			if eq, ok := expr.(clause.AndConditions); ok {
				exprs = append(exprs, eq.Exprs...)
			} else if eq, ok := expr.(clause.Eq); ok {

					stmt.AddClause(clause.Where{Exprs: []clause.Expression{clause.IN{Column: column, Values: values}}})
				}
			}
		case reflect.Struct:
			for _, field := range stmt.Schema.PrimaryFields {
				if value, isZero := field.ValueOf(stmt.Context, stmt.ReflectValue); !isZero {
					stmt.AddClause(clause.Where{Exprs: []clause.Expression{clause.Eq{Column: field.DBName, Value: value}}})
				}
			}

		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.Or(clause.Gt{Column: "score", Value: 100}, clause.Like{Column: "name", Value: "%linus%"}),

			optimizer.ModifyStatement(tx.Statement)
		} else {
			whereConds = append(whereConds, cond)
		}
	}

	if len(whereConds) > 0 {
		tx.Statement.AddClause(clause.Where{Exprs: tx.Statement.BuildCondition(whereConds[0], whereConds[1:]...)})
	}
	return
}

var tableRegexp = regexp.MustCompile(`(?i)(?:.+? AS (\w+)\s*(?:$|,)|^\w+\s+(\w+)$)`)

											}

											exprs = append(exprs, clause.Expr{SQL: onSQL, Vars: vars})
										}
									}
								}
							}

							return clause.Join{
								Type:  joinType,
								Table: clause.Table{Name: relation.FieldSchema.Table, Alias: tableAliasName},
								ON:    clause.Where{Exprs: exprs},
							}
						}

						parentTableName := clause.CurrentTable