Strange queries every 10 seconds to DB

[Misha]

Does anybody know why there are queries SHOW FULL TABLES FROM `ARM`
LIKE 'PROBABLYNOT' in a MySQL general log?
What process sends them?

What I could see in the log of DB is that play keeps 8 connections
with the DB and sends this query every 10 seconds on every connection.
But I couldn't catch any sight at the application side, even with log
level set to TRACE

I have play 1.2.3, MySQL 5.1.58

[Brian Nesbitt]

Are you using a database named ARM?  Are you just using the default Play install otherwise?  Not much in google about this.  Probably something dumb (not by you, I mean just in general).

[Misha]

Hello, Brian!

Yes, the database name is ARM. My application uses this database. So
when I stop the application, MySQL stops receiving query SHOW FULL
TABLES FROM `ARM` LIKE 'PROBABLYNOT'.
Yes, I use default Play installation, no other libraries.

[Brian Nesbitt]

Found it... its the connection pooling checking the connection.

Play uses the popular http://sourceforge.net/projects/c3p0/ for its connection pool.

Take a look at activeCheckConnectionNoQuery() in the DefaultConnectionTester.java:

http://c3p0.hg.sourceforge.net/hgweb/c3p0/c3p0/file/5cdc51990221/src/java/com/mchange/v2/c3p0/impl/DefaultConnectionTester.java#l187

rs = c.getMetaData().getTables( null, null, "PROBABLYNOT", new String[] {"TABLE"} );

return CONNECTION_IS_OKAY;

[Misha]

Many thanks, Brian! I appreciate your help