| Bug #111241 | Wrong result of `IN` clause | ||
|---|---|---|---|
| Submitted: | 1 Jun 2023 11:39 | Modified: | 1 Jun 2023 13:45 |
| Reporter: | chi zhang | Email Updates: | |
| Status: | Verified | Impact on me: | |
| Category: | MySQL Server: DML | Severity: | S3 (Non-critical) |
| Version: | Last commit version in github https://gi | OS: | Any |
| Assigned to: | CPU Architecture: | Any | |
| Tags: | Logic bug | ||
[1 Jun 2023 13:45]
MySQL Verification Team
Hi Mr. zhang, Thank you for your bug report. We have tested your test case on the regular 8.0.33 and got the following results: +------------+ | MIN(t0.c0) | +------------+ | 1 | +------------+ +------+ | c0 | +------+ | 1 | +------+ +------+ | c0 | +------+ | | +------+ We agree with your logic and we are verifying your report. Verified.
Description: Consider the following program: ``` CREATE TABLE t0(c0 BOOL); INSERT INTO t0 VALUES (true); SELECT MIN(t0.c0) FROM t0 ; # 1 SELECT t0.c0 FROM t0 WHERE (('0')NOT REGEXP((((t0.c0))NOT LIKE(CASE t0.c0 WHEN 76 THEN 0.7 ELSE t0.c0 END )))AND( t0.c0 IN ((1)))); # 1 SELECT t0.c0 FROM t0 WHERE (('0')NOT REGEXP((((t0.c0))NOT LIKE(CASE t0.c0 WHEN 76 THEN 0.7 ELSE t0.c0 END )))AND( t0.c0 IN (SELECT MIN(t0.c0) FROM t0 ))); # empty result ``` The first query return `1`, the second query is equivalent to the third one, because I just replace the `IN` clause from a concrete number to a subquery. So they should have the same results, but the second query return `1`, while the third query return an empty result. I believe the second query generate a wrong result. Because `(('0')NOT REGEXP((((t0.c0))NOT LIKE(CASE t0.c0 WHEN 76 THEN 0.7 ELSE t0.c0 END ))))` should equal to false, so even `t0.c0 IN ((1))` equals to true, the whole condition should be false. How to repeat: I clone mysql source code from github https://github.com/mysql/mysql-server/commit/ea7087d885006918ad54458e7aad215b1650312c, and build it in ubuntu. This is the configure command `cmake -DCMAKE_INSTALL_PREFIX=/usr/local/mysql -DMYSQL_DATADIR=/usr/local/mysql/data -DDOWNLOAD_BOOST=1 -DWITH_BOOST=/tmp/boost -DFORCE_INSOURCE_BUILD=ON` Suggested fix: The second and third queries should have the same results.