| Bug #20732 | Partial index and long sjis search with '>' fails sometimes | ||
|---|---|---|---|
| Submitted: | 27 Jun 2006 20:48 | Modified: | 13 Nov 2006 18:55 |
| Reporter: | Peter Gulutzan | Email Updates: | |
| Status: | Closed | Impact on me: | |
| Category: | MySQL Server | Severity: | S3 (Non-critical) |
| Version: | 4.1 | OS: | Any (all) |
| Assigned to: | Ramil Kalimullin | CPU Architecture: | Any |
[28 Jun 2006 16:35]
MySQL Verification Team
Thank you for the bug report.
[28 Sep 2006 6:45]
Bugs System
A patch for this bug has been committed. After review, it may be pushed to the relevant source trees for release in the next version. You can access the patch from: http://lists.mysql.com/commits/12679 ChangeSet@1.2539, 2006-09-28 11:43:40+05:00, ramil@mysql.com +3 -0 Fix for bug #20732: Partial index and long sjis search with '>' fails sometimes We miss some records sometimes using RANGE method if we have partial key segments. Example: create table t1(a char(2), key(a(1))); insert into t1 values ('a'), ('xx'); select a from t1 where a > 'x'; We call index_read() passing 'x' key and HA_READ_AFTER_KEY flag in the handler::read_range_first() wich is wrong because we have a partial key segment for the field and might miss records like 'xx'. Fix: don't use open segments in such a case.
[19 Oct 2006 7:52]
Bugs System
A patch for this bug has been committed. After review, it may be pushed to the relevant source trees for release in the next version. You can access the patch from: http://lists.mysql.com/commits/13940 ChangeSet@1.2578, 2006-10-19 12:52:37+05:00, ramil@mysql.com +6 -0 Fix for bug #20732: Partial index and long sjis search with '>' fails sometimes We miss some records sometimes using RANGE method if we have partial key segments. Example: Create table t1(a char(2), key(a(1))); insert into t1 values ('a'), ('xx'); select a from t1 where a > 'x'; We call index_read() passing 'x' key and HA_READ_AFTER_KEY flag in the handler::read_range_first() wich is wrong because we have a partial key segment for the field and might miss records like 'xx'. Fix: don't use open segments in such a case.
[13 Nov 2006 18:55]
Paul DuBois
Noted in 4.1.23, 5.0.30 (5.0.29), 5.1.13 changelogs. Range searches on columns with an index prefix could miss records.
Description: I create a table with a long SJIS column. The table has a partial index with maximum length = 500. There is no error during creation. I insert a long string containing Katakana characters. I try to search against this string using '>'. The search fails. How to repeat: mysql> create table t88 (s1 varchar(600) character set sjis, key(s1(500))); Query OK, 0 rows affected (0.33 sec) mysql> set names utf8; Query OK, 0 rows affected (0.00 sec) mysql> insert into t88 values ('a'),('b'),('c'),(repeat('グ',600)); Query OK, 4 rows affected (0.00 sec) Records: 4 Duplicates: 0 Warnings: 0 mysql> select count(*) from t88 where s1 = repeat('グ',600); +----------+ | count(*) | +----------+ | 1 | +----------+ 1 row in set (0.01 sec) mysql> select count(*) from t88 where s1 > repeat('グ',500); +----------+ | count(*) | +----------+ | 0 | +----------+ 1 row in set (0.00 sec)