expression: fix incorrect date arithmitical with negative interval #8523
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Hi contributor, thanks for your PR. This patch needs to be approved by someone of admins. They should reply with "/ok-to-test" to accept this PR for running test automatically. |
| {date[0], fcSub, -0.5, date[1]}, | ||
| {date[0], fcSub, -1.4, date[1]}, | ||
| } | ||
| for _, test := range tests { |
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Using test is consistent with other usages in this file.
| @@ -1527,7 +1527,7 @@ func extractSingleTimeValue(unit string, format string) (int64, int64, int64, fl | |||
| if err != nil { | |||
| return 0, 0, 0, 0, ErrIncorrectDatetimeValue.GenWithStackByArgs(format) | |||
| } | |||
| iv := int64(fv + 0.5) | |||
| iv := int64(math.Round(fv)) | |||
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Should we use floatStrToIntStr instead of Round? floatStrToIntStr does round operation also and it covers corner cases.
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The float value is also needed.
iv is used in cases that float value should be rounded, like DAY, WEEK.
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You mean inputs like 1.23a4 DAY ? 1.23a can pass strconv.ParseFloat @eurekaka
or something like 1e9223372036854775807 ?
I think the change here is ok, a sane person will not use those illegal input, so
strconv.ParseFloat + math.Round is suitable for most of the cases
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MySQL(root@127.0.0.1:test) > select adddate("2018-12-09", interval "1e1" DAY);
+-------------------------------------------+
| adddate("2018-12-09", interval "1e1" DAY) |
+-------------------------------------------+
| 2018-12-10 |
+-------------------------------------------+
1 row in set, 1 warning (0.00 sec)
MySQL(root@127.0.0.1:test) > select adddate("2018-12-09", interval "10" DAY);
+------------------------------------------+
| adddate("2018-12-09", interval "10" DAY) |
+------------------------------------------+
| 2018-12-19 |
+------------------------------------------+
1 row in set (0.00 sec)
MySQL(root@127.0.0.1:test) > select adddate("2018-12-09", interval "9223372036854775807" DAY);
+-----------------------------------------------------------+
| adddate("2018-12-09", interval "9223372036854775807" DAY) |
+-----------------------------------------------------------+
| NULL |
+-----------------------------------------------------------+
1 row in set, 1 warning (0.00 sec)
MySQL(root@127.0.0.1:test) > show warnings;
+---------+------+--------------------------------------------+
| Level | Code | Message |
+---------+------+--------------------------------------------+
| Warning | 1441 | Datetime function: datetime field overflow |
+---------+------+--------------------------------------------+
1 row in set (0.01 sec)We should use strconv.ParseFloat() in this PR. floatStrToIntStr converts 1e1 to 10, which is not in MySQL. Another discovery is that TiDB does not properly handle the "Datetime function: datetime field overflow" warning:
TiDB(root@127.0.0.1:test) > select adddate("2018-12-09", interval "9223372036854775807" DAY);
+-----------------------------------------------------------+
| adddate("2018-12-09", interval "9223372036854775807" DAY) |
+-----------------------------------------------------------+
| 2018-12-09 |
+-----------------------------------------------------------+
1 row in set (0.00 sec)There was a problem hiding this comment.
You can do it in the next PR, this PR LGTM
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LGTM |
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Ping |
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@zz-jason PTAL |
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/run-all-tests |
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@lerencao Please cherry-pick this commit to release-2.1 and release-2.0 branch, thanks. |
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Got it! |
What problem does this PR solve?
#8497
What is changed and how it works?
Round the float interval, so that the date arithmetical can behave like mysql:
Check List
Tests
Related changes
This bug affects almost all functions related to date arithmetical functions. May be it should
This change is