Bug #57009 table name case sensitivity of performance_schema vs. information_schema

• Submitted: 24 Sep 2010 15:45
• Reporter: Axel Schwenke
• Status: Verified
• Category: MySQL Server: Information schema
• Severity: S4 (Feature request)
• Version: 5.5.6
• OS: Any
• CPU Architecture: Any

[24 Sep 2010 15:45] Axel Schwenke

Description:
Table names in performance_schema are case sensitive, but in information_schema are not. This is not consistent. Not sure if information_schema is wrong or performance_schema. The `mysql` database is case sensitive again.

How to repeat:
select count(*) from INFORMATION_SCHEMA.TABLES;
+----------+
| count(*) |
+----------+
|       51 |
+----------+
1 row in set (0,00 sec)

select count(*) from INFORMATION_SCHEMA.tables;
+----------+
| count(*) |
+----------+
|       51 |
+----------+
1 row in set (0,00 sec)

vs:

select count(*) from performance_schema.THREADS;
+----------+
| count(*) |
+----------+
|       50 |
+----------+
1 row in set (0.00 sec)

select count(*) from performance_schema.threads;
ERROR 1146 (42S02): Table 'performance_schema.threads' doesn't exist

Suggested fix:
Case sensitivity rules should be consistent for system tables.

[29 Sep 2010 8:11] Kristian Köhntopp

"The `mysql` database is case sensitive again."

This is dependent on the file system and the lower_case_table_names setting.

[21 Oct 2010 16:35] Peter Laursen

worse than that!

Even on Windows with 'lower_case_table_names = 1', I_S' tables are UPPERCASE.  http://dev.mysql.com/doc/refman/5.0/en/identifier-case-sensitivity.html "Table names are stored in lowercase on disk and name comparisons are not case sensitive" (now you may say the I_S tables are not "stored" - but it is still an inconsistency!)

With 'lower_case_table_names = 2' and MySQL 5.5.6 on Windows, I_S tables UPPERCASE and P_S tables are lowercase.