SHOW VARIABLES LIKE 'max_allowed_packet'; 
+--------------------+---------+ 
¦ Variable_name......¦ Value...¦ 
+--------------------+---------+ 
¦ max_allowed_packet ¦ 1047552 ¦ 
+--------------------+---------+ 

> Does anyone know if there's a maximum query length in mysql 4.1.x?
>
> Thanks!


The max is the length of your "max_allowed_packet" setting. You can up it
permanently or only when needed in order to deal with queries up to either
16MB or 1GB (depending on your version).

http://dev.mysql.com/doc/mysql/en/server-system-variables.html
http://dev.mysql.com/doc/mysql/en/program-options.html