mirror of
https://github.com/MariaDB/server.git
synced 2025-01-18 13:02:28 +01:00
f4ff086abe
PROBLEMS Description:- Server variable "--lower_case_tables_names" when set to "0" on windows platform which does not support case sensitive file operations leads to problems. A warning message is printed in the error log while starting the server with "--lower_case_tables_names=0". Also according to the documentation, seting "lower_case_tables_names" to "0" on a case-insensitive filesystem might lead to index corruption. Analysis:- The problem reported in the bug is:- Creating an INNODB table 'a' and executing a query, "INSERT INTO a SELECT a FROM A;" on a server started with "--lower_case_tables_names=0" and running on a case-insensitive filesystem leads innodb to flat spin. Optimizer thinks that "a" and "A" are two different tables as the variable "lower_case_table_names" is set to "0". As a result, optimizer comes up with a plan which does not need a temporary table. If the same table is used in select and insert, a temporary table is needed. This incorrect optimizer plan leads to infinite insertions. Fix:- If the server is started with "--lower_case_tables_names" set to 0 on a case-insensitive filesystem, an error, "The server option 'lower_case_table_names'is configured to use case sensitive table names but the data directory is on a case-insensitive file system which is an unsupported combination. Please consider either using a case sensitive file system for your data directory or switching to a case-insensitive table name mode.", is printed in the server error log and the server exits. |
||
|---|---|---|
| .. | ||
| include | ||
| r | ||
| std_data | ||
| t | ||