Error message for DECIMAL overflow is just "ERROR 1690 (22003): %s value is out of range in '%s'"

[kennytm]

Bug Report

Please answer these questions before submitting your issue. Thanks!

1. Minimal reproduce step (Required)

select cast(9e40 as decimal(65)) * cast(9e40 as decimal(65));

2. What did you expect to see? (Required)

ERROR 1690 (22003): DECIMAL value is out of range in '(cast(9e40 as decimal(65,0)) * cast(9e40 as decimal(65,0)))'

3. What did you see instead (Required)

ERROR 1690 (22003): %s value is out of range in '%s'

4. What is your TiDB version? (Required)

Both master and v5.1.1.

Release Version: v5.3.0-alpha-77-g5fb3cd42f
Edition: Community
Git Commit Hash: 5fb3cd42f7ab7460adb2b3196c62bd6c7a903823
Git Branch: master
UTC Build Time: 2021-09-11 09:24:20
GoVersion: go1.17
Race Enabled: false
TiKV Min Version: v3.0.0-60965b006877ca7234adaced7890d7b029ed1306
Check Table Before Drop: false

[unconsolable]

I tried to fill the error args as follows in (*builtinArithmeticMultiplyDecimalSig).vecEvalDecimal

if terror.ErrorEqual(err, types.ErrOverflow) {
	return types.ErrOverflow.GenWithStackByArgs("DECIMAL", fmt.Sprintf("(%s * %s)", b.args[0].String(), b.args[1].String()))
}

But the error is still not the same as expected

ERROR 1690 (22003): DECIMAL value is out of range in '(90000000000000000000000000000000000000000 * 90000000000000000000000000000000000000000)'

But I found that for BIGINT UNSIGNED the error is incompatible with MySQL either.

tidb> select cast(9e40 as unsigned) * cast(9e40 as unsigned);
ERROR 1690 (22003): BIGINT UNSIGNED value is out of range in '(18446744073709551615 * 18446744073709551615)'
mysql> select cast(9e40 as unsigned) * cast(9e40 as unsigned);
ERROR 1690 (22003): BIGINT UNSIGNED value is out of range in '(cast(9e40 as unsigned) * cast(9e40 as unsigned))'

[kennytm]

i think it is fine as long as the error doesn't literally say %s.

[kennytm]

Note that this error affects more than *. All arithmetic operators should be checked.

examples:

set @a = cast(9e40 as decimal(65)) * cast(9e39 as decimal(65));

select @a + @a;
-- EXPECTED: ERROR 1690 (22003): DECIMAL value is out of range in '((@`a`) + (@`a`))'
-- ACTUAL:   ERROR 1690 (22003): %s value is out of range in '%s'
select @a - (-@a);
-- EXPECTED: ERROR 1690 (22003): DECIMAL value is out of range in '((@`a`) - -((@`a`)))'
-- ACTUAL:   ERROR 1690 (22003): %s value is out of range in '%s'
select @a / 0.1;
-- EXPECTED: ERROR 1690 (22003): DECIMAL value is out of range in '((@`a`) / 0.1)'
-- ACTUAL:   ERROR 1690 (22003): %s value is out of range in '%s'

[github-actions]

Please check whether the issue should be labeled with 'affects-x.y' or 'fixes-x.y.z', and then remove 'needs-more-info' label.