)

	// optimize match english letters and midline
	// The following code is basically called in for.
	// In order to avoid the performance problems caused by repeated compilation of regular expressions,
	// it only needs to be done once outside, so optimization is done here.
	if idx != -1 && regEnLetterAndMidline.MatchString(str[0:idx]) {
		name = str[0:idx]
	} else {

		if c, ok := stmt.Clauses["WHERE"]; ok {
			if where, ok := c.Expression.(clause.Where); ok && len(where.Exprs) >= 1 {
				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
					}
				}
			}
		}

			}, 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"}}},
						clause.NamedExpr{"?", []interface{}{clause.Column{Name: "name"}}},

		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%"}),
			}},

							}
						}
					} else {
						fromClause.Joins = append(fromClause.Joins, clause.Join{
							Expression: clause.NamedExpr{SQL: join.Name, Vars: join.Conds},
						})
					}
				} else {
					fromClause.Joins = append(fromClause.Joins, clause.Join{
						Expression: clause.NamedExpr{SQL: join.Name, Vars: join.Conds},
					})
				}
			}

			db.Statement.AddClause(fromClause)

				return
			}
		}

		if clause, ok := tx.Statement.Clauses["SELECT"]; ok {
			clause.Expression = nil
			tx.Statement.Clauses["SELECT"] = clause
		}
	case string:
		if strings.Count(v, "?") >= len(args) && len(args) > 0 {
			tx.Statement.AddClause(clause.Select{
				Distinct:   db.Statement.Distinct,
				Expression: clause.Expr{SQL: v, Vars: args},
			})
		} else if strings.Count(v, "@") > 0 && len(args) > 0 {

	{"3<<(2+4)", 3 << (2 + 4), true},
	// Junk at EOF.
	{"3 x", 3, false},
	// Big number
	{"4611686018427387904", 4611686018427387904, true},
}

func TestExpr(t *testing.T) {
	p := NewParser(nil, nil, nil) // Expression evaluation uses none of these fields of the parser.
	for i, test := range exprTests {
		p.start(lex.Tokenize(test.input))
		result := int64(p.expr())
		if result != test.output {

	}

	for _, join := range from.Joins {
		builder.WriteByte(' ')
		join.Build(builder)
	}
}

// MergeClause merge from clause
func (from From) MergeClause(clause *Clause) {
	clause.Expression = from

	}

	if locking.Options != "" {
		builder.WriteByte(' ')
		builder.WriteString(locking.Options)
	}
}

// MergeClause merge order by clauses
func (locking Locking) MergeClause(clause *Clause) {
	clause.Expression = locking

	}
}

// MergeClause merge assignments clauses
func (set Set) MergeClause(clause *Clause) {
	copiedAssignments := make([]Assignment, len(set))
	copy(copiedAssignments, set)
	clause.Expression = Set(copiedAssignments)
}

func Assignments(values map[string]interface{}) Set {
	keys := make([]string, 0, len(values))
	for key := range values {
		keys = append(keys, key)
	}
	sort.Strings(keys)