It looks like Hibernate is not able to set the hibernate.c3p0.max_statements property in my application. Here is my hibernateProperties from spring config




The spring datasource config is :-


With maxStatements commented in datasource, I expect the hibernateProperties hibernate.c3p0.max_statements to be active. However the following log shows the Hibernate default value for max statements which is 0

2007-05-08 13:53:47,212 INFO [com.mchange.v2.c3p0.impl.AbstractPoolBackedDataSource] - Initializing c3p0 pool... com.mchange.v2.c3p0.ComboPooledDataSource [ acquireIncrement -> 3, acquireRetryAttempts -> 3, acquireRetryDelay -> 1000, autoCommitOnClose -> false, automaticTestTable -> null, breakAfterAcquireFailure -> false, checkoutTimeout -> 0, connectionCustomizerClassName -> null, connectionTesterClassName -> com.mchange.v2.c3p0.impl.DefaultConnectionTester, dataSourceName -> 17g3ycg7mtmnwdimi191y|1284fd4, debugUnreturnedConnectionStackTraces -> false, description -> null, driverClass -> oracle.jdbc.driver.OracleDriver, factoryClassLocation -> null, forceIgnoreUnresolvedTransactions -> false, identityToken -> 17g3ycg7mtmnwdimi191y|1284fd4, idleConnectionTestPeriod -> 0, initialPoolSize -> 3, jdbcUrl -> jdbc:oracle:thin:@localhost:1521:xxxx, lastAcquisitionFailureDefaultUser -> null, maxAdministrativeTaskTime -> 0, maxConnectionAge -> 0, maxIdleTime -> 0, maxIdleTimeExcessConnections -> 0, maxPoolSize -> 15, maxStatements -> 0, maxStatementsPerConnection -> 5, minPoolSize -> 3, numHelperThreads -> 3, numThreadsAwaitingCheckoutDefaultUser -> 0, preferredTestQuery -> null, properties -> {user=******, password=******}, propertyCycle -> 0, testConnectionOnCheckin -> false, testConnectionOnCheckout -> false, unreturnedConnectionTimeout -> 0, usesTraditionalReflectiveProxies -> false ]


When maxStatements in datasource configuration is uncommented, the max statements are configured correctly to 15 as defined in the datasource.

From what i understand, some of the c3p0 properties must be explicitly mentioned in the hibernate config, to prevent from using hibernate defaults over the actual c3p0 properties. In this case, why is Hibernate not able to set hibernate.c3p0.max_statements? I am using Hibernate 3. Am I missing something?

Thanks,
Nik

Actually, it makes more sense to configure statement cache per connection, rather than globally. At this point I am just curios to know why the maxstatements hibernate property is not working for me.

Thanks,
Nik

I ran into a similar situation when I set Hibernate to use a JNDI DataSource. Suddenly it started using DatasourceConnectionProvider instead of C3P0ConnectionProvider. Hibernate's c3p0 defaults and hibernate.c3p0.* properties are only active when using C3P0ConnectionProvider. It is trivial to use c3p0 to pool connections from a DataSource, but I guess Hibernate just isn't written that way.

Most Spring users configure Hibernate using Spring's LocalSessionFactoryBean. If LocalSessionFactoryBean is provided with a DataSource then it configures Hibernate to use a Spring ConnectionProvider (LocalDataSourceConnectionProvider or TransactionAwareDataSourceConnectionProvider as appropriate). Therefore, similar to above, C3P0ConnectionProvider does not get used.

Note that the c3p0 default for max statements is also 0. The 0 you see is probably from that instead of Hibernate:
http://www.mchange.com/projects/c3p0/in ... Statements

<prop key="hibernate.c3p0.max_statements">15</prop> is a hibernate property for C3P0, which means that this will override the C3P0 default and should use the hibernate one, i.e max_statements must be 15. However, inspite of configuring this it does take any effect. The rest of the C3P0 properties which are configured as hibernate properties work well.

Not according to your first post. Three other properties from the configuration you posted are being ignored:
><prop key="hibernate.c3p0.min_size">10</prop>
...
>minPoolSize -> 3

><prop key="hibernate.c3p0.max_size">50 </prop>
...
>maxPoolSize -> 15

><prop key="hibernate.c3p0.idle_test_period">300</prop>
...
>idleConnectionTestPeriod -> 0

The remaining two are inconclusive. You set them to the default values, so there would be no change either way. Defaults listed here:
http://www.mchange.com/projects/c3p0/in ... axIdleTime
http://www.mchange.com/projects/c3p0/in ... eIncrement