25.2. Logging

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Whenever you&#8217;re using a framework that generates SQL statements on your behalf, you have to ensure that the generated statements are the ones that you intended in the first place.

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There are several alternatives to logging statements.
You can log statements by configuring the underlying logging framework.
For Log4j, you can use the following appenders:

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<pre class="prettyprint highlight">`### log just the SQL
log4j.logger.org.hibernate.SQL=debug

### log JDBC bind parameters ###
log4j.logger.org.hibernate.type=trace
log4j.logger.org.hibernate.type.descriptor.sql=trace`</pre>
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However, there are some other alternatives like using datasource-proxy or p6spy.
The advantage of using a JDBC `Driver` or `DataSource` Proxy is that you can go beyond simple SQL logging:

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• statement execution time
• JDBC batching logging

• database connection monitoring </div>

  Another advantage of using a DataSource proxy is that you can assert the number of executed statements at test time. This way, you can have the integration tests fail when a N+1 query issue is automatically detected.

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  While simple statement logging is fine, using datasource-proxy or p6spy is even better.

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