Description:
A number of server options are defined in mysqld.cc as having MAX_ULONG for their maximum (and sometimes default) values; the values shown in the Manual for such options are correct only for 32-bit systems.
A number of these discrepancies have been reported by Support. Rather than address them piecemeal, it's preferable to fix the underlying problem in one go.
How to repeat:
Check the source.
Verify in mysql client on 64-bit OS.
Example:
[from mysqld.cc in 6.0 bzr tree]
{ "group_concat_max_len", OPT_GROUP_CONCAT_MAX_LEN,
"The maximum length of the result of function group_concat.",
(uchar**) &global_system_variables.group_concat_max_len,
(uchar**) &max_system_variables.group_concat_max_len, 0, GET_ULONG,
REQUIRED_ARG, 1024, 4, (longlong) ULONG_MAX, 0, 1, 0},
[in mysql client/server built from 6.0-bzr]
mysql> show variables like 'version%';
+-------------------------+---------------------+
| Variable_name | Value |
+-------------------------+---------------------+
| version | 6.0.10 |
| version_comment | Source distribution |
| version_compile_machine | x86_64 |
| version_compile_os | suse-linux-gnu |
+-------------------------+---------------------+
4 rows in set (0.00 sec)
mysql> set @@group_concat_max_len = 18446744073709547520;
Query OK, 0 rows affected (0.00 sec)
mysql> show variables like 'group%';
+----------------------+----------------------+
| Variable_name | Value |
+----------------------+----------------------+
| group_concat_max_len | 18446744073709547520 |
+----------------------+----------------------+
1 row in set (0.00 sec)
Suggested fix:
Check mysqld.cc for all server options having maximum and/or default values defined using MAX_ULONG.
Fix corresponding entries in mysqld.xml optvars file to show these values as 4294967295 (4GB) for 32-bit platforms and 18446744073709547520 (16PB) for 64-bit platforms.
(MC made fixes in the optvars DTD and docs build system last week to handle such cases, which it didn't before.)
Description: A number of server options are defined in mysqld.cc as having MAX_ULONG for their maximum (and sometimes default) values; the values shown in the Manual for such options are correct only for 32-bit systems. A number of these discrepancies have been reported by Support. Rather than address them piecemeal, it's preferable to fix the underlying problem in one go. How to repeat: Check the source. Verify in mysql client on 64-bit OS. Example: [from mysqld.cc in 6.0 bzr tree] { "group_concat_max_len", OPT_GROUP_CONCAT_MAX_LEN, "The maximum length of the result of function group_concat.", (uchar**) &global_system_variables.group_concat_max_len, (uchar**) &max_system_variables.group_concat_max_len, 0, GET_ULONG, REQUIRED_ARG, 1024, 4, (longlong) ULONG_MAX, 0, 1, 0}, [in mysql client/server built from 6.0-bzr] mysql> show variables like 'version%'; +-------------------------+---------------------+ | Variable_name | Value | +-------------------------+---------------------+ | version | 6.0.10 | | version_comment | Source distribution | | version_compile_machine | x86_64 | | version_compile_os | suse-linux-gnu | +-------------------------+---------------------+ 4 rows in set (0.00 sec) mysql> set @@group_concat_max_len = 18446744073709547520; Query OK, 0 rows affected (0.00 sec) mysql> show variables like 'group%'; +----------------------+----------------------+ | Variable_name | Value | +----------------------+----------------------+ | group_concat_max_len | 18446744073709547520 | +----------------------+----------------------+ 1 row in set (0.00 sec) Suggested fix: Check mysqld.cc for all server options having maximum and/or default values defined using MAX_ULONG. Fix corresponding entries in mysqld.xml optvars file to show these values as 4294967295 (4GB) for 32-bit platforms and 18446744073709547520 (16PB) for 64-bit platforms. (MC made fixes in the optvars DTD and docs build system last week to handle such cases, which it didn't before.)