| Bug #8093 | GROUP BY can alter some values of a grouped by column | ||
|---|---|---|---|
| Submitted: | 22 Jan 2005 20:08 | Modified: | 24 Jan 2005 17:19 |
| Reporter: | paul van den berg | Email Updates: | |
| Status: | Closed | Impact on me: | |
| Category: | MySQL Server: MyISAM storage engine | Severity: | S3 (Non-critical) |
| Version: | 4.1.8 | OS: | Any (*) |
| Assigned to: | Sergey Petrunya | CPU Architecture: | Any |
[23 Jan 2005 12:53]
Aleksey Kishkin
tested on windows and linux 4.1 and 5.0
[24 Jan 2005 13:35]
paul van den berg
Section 12.2 of the manual states: IF(expr1,expr2,expr3) Expression Return Value expr2 or expr3 returns a string string expr2 or expr3 returns an integer integer What happens if expr2 returns a string and expr3 returns an integer? Mysqlserver gets confused, and the documentation is self-contradicting..
[24 Jan 2005 14:12]
Aleksey Kishkin
Thank you for your bug report. This issue has already been fixed in the latest released version of that product, which you can download at http://www.mysql.com/downloads/ Additional info: tested on 4.1.9-ga - works properly, shows '-1', so, this bug doesn't exist in latest release.
Description: create table t (c char(1) not null); insert into t values (''),('0'),('1'); select if(c regexp '[0-9]{1}',c,-1) as i from t; +----+ | i | +----+ | -1 | | 0 | | 1 | +----+ select if(c regexp '[0-9]{1}',c,-1) as i from t group by c; +---+ | i | +---+ | - | | 0 | | 1 | +---+ select if(c regexp '[0-9]{1}',c,-1) as i from t group by i; +---+ | i | +---+ | - | | 0 | | 1 | +---+ How to repeat: See description Suggested fix: not a fix, but a workaround: select if(c regexp '[0-9]{1}',c,'-1') as i from t group by i;