How to change max_allowed_packet size

mysql
Muleskinner picture Muleskinner · Nov 9, 2011 · Viewed 852.3k times · Source

I am having a problem with BLOB fields in my MySQL database - when uploading files larger than approx 1MB I get an error Packets larger than max_allowed_packet are not allowed.

Here is what i've tried:

In MySQL Query Browser I ran a show variables like 'max_allowed_packet' which gave me 1048576.

Then I execute the query set global max_allowed_packet=33554432 followed by show variables like 'max_allowed_packet' - it gives me 33554432 as expected.

But when I restart the MySQL server it magically goes back to 1048576. What am I doing wrong here?

Bonus question, is it possible to compress a BLOB field?

Answer

Manuel picture Manuel · Nov 9, 2011

Change in the my.ini or ~/.my.cnf file by including the single line under [mysqld] or [client] section in your file:

max_allowed_packet=500M

then restart the MySQL service and you are done.

See the documentation for further information.

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