Bug #47704 | hash index on VARCHAR prefix not working correctly | ||
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Submitted: | 29 Sep 2009 9:13 | Modified: | 6 Mar 2012 1:23 |
Reporter: | Axel Schwenke | Email Updates: | |
Status: | Closed | Impact on me: | |
Category: | MySQL Server: Memory storage engine | Severity: | S2 (Serious) |
Version: | 5.0.86, 5.1.39 | OS: | Linux |
Assigned to: | CPU Architecture: | Any |
[29 Sep 2009 9:13]
Axel Schwenke
[29 Nov 2009 5:43]
zhiwen xiao
test on 5.1.36
Attachment: patch.txt (text/plain), 1.90 KiB.
[29 Nov 2009 5:52]
zhiwen xiao
heap hash index on a column prefix build hash value on full column and search with prefix. following patch may work, not verified. http://bugs.mysql.com/file.php?id=13447
[6 Mar 2012 1:23]
Paul DuBois
Noted in 5.6.5 changelog. For MEMORY tables, a scan of a HASH index on a VARCHAR column could fail to find some rows if the index was on a prefix of the column.