Bug #15590 Wrong work of CONCAT() function
Submitted: 8 Dec 2005 15:08 Modified: 8 Dec 2005 15:19
Reporter: Ildar Habipov Email Updates:
Status: Closed Impact on me:
None 
Category:MySQL Server Severity:S3 (Non-critical)
Version:4.1.8 OS:Microsoft Windows (Windows XP SP2)
Assigned to: Aleksey Kishkin CPU Architecture:Any

[8 Dec 2005 15:08] Ildar Habipov
Description:
CONCAT() function return null if parameters summary length is greater than 1047552

How to repeat:
SQL query SELECT CONCAT( LPAD( '' , 523776 , 'a' ) , LPAD( '' , 523777 , 'a' ) ) will return NULL
[8 Dec 2005 15:19] Ildar Habipov
Sorry... it wasn't bug.
It depends on MySQL option 'max_allowed_packet' in configuration file in my case it was set to 1M.