Bug #34878 Few variables have default value according to documentation but error occurs

• Submitted: 27 Feb 2008 11:53
• Modified: 13 Nov 10:43
• Reporter: Salman Rawala
• Status: Patch pending
• Category: Server: DML
• Severity: S3 (Non-critical)
• Version: 5.1.22, 5.1.23
• OS: Any
• Assigned to: Sergei Golubchik
• Tags: Invalid default value
• Triage: Triaged: D4 (Minor)

[27 Feb 2008 11:53] Salman Rawala

Description:
There are few variables that are giving errors on assigning DEFAULT value to variable,
but according to documentation, they have default value. These variales are:

max_connect_errors, max_connections, delay_key_write, log_output, flush, key_buffer_size,
key_cache_age_threshold, key_cache_block_size, key_cache_division_limit, max_binlog_size
g

How to repeat:
Sample Code:
SET @@global.key_buffer_size = 99;
--Error ER_NO_DEFAULT
SET @@global.key_buffer_size = DEFAULT;

Actual Output:
SET @@global.key_buffer_size = 99;
SET @@global.key_buffer_size = DEFAULT;
ERROR 42000: Variable 'key_buffer_size' doesn't have a default value

[27 Feb 2008 12:15] Valeriy Kravchuk

Indeed, some of these variables does NOT accept DEFAULT as value.

[7 Aug 16:33] Sergei Golubchik

will be fixed in WL#4738