Method valuesEqual

server/expression/in_subquery.go:131–148

valuesEqual returns true if the left value is equal to the row provided using the equality functions previously assigned to |compFuncs| during analysis. If the left value is a single scalar, then |row| has a single value as well. Otherwise, (left is a tuple), |row| has a matching number of values.

(ctx *sql.Context, left interface{}, row sql.Row)

// assigned to |compFuncs| during analysis. If the left value is a single scalar, then |row| has a single value as
// well. Otherwise, (left is a tuple), |row| has a matching number of values.
func (in *InSubquery) valuesEqual(ctx *sql.Context, left interface{}, row sql.Row) (bool, error) {
	// Note that we have to edit the literals in place, since the comparison functions reference them directly.
	in.leftLiteral.Val = left
	for i, v := range row {
		in.rightLiterals[i].Val = v
	}

	for _, compFunc := range in.compFuncs {
		result, err := compFunc.Eval(ctx, nil)
		if err != nil {
			return false, err
		}
		if !result.(bool) {
			return false, nil
		}
	}
	return true, nil
}

// IsNullable implements the sql.Expression interface.
func (in *InSubquery) IsNullable(ctx *sql.Context) bool {