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Hibernate database queries

I am having a problem with the number of queries made asleep to the database. Here is my query log (using Mysql 5.1) to the database when performing a simple selection:

111125  7:18:30
27 Query    SET autocommit=0
27 Query    SELECT @@session.tx_isolation
27 Query    select this_.id as id34_0_, this_.media_id as media3_34_0_, this_.message as message34_0_, this_.user_id as user4_34_0_ from notifications this_
27 Query    rollback
27 Query    SET autocommit=1

I read a lot about how to set autocommit to 0, and then to 1. I know that the default value for the connection is 1, and this behavior cannot be changed. You can run SET autocommit = 0, but the result will be the same.

Anyway, to avoid any of these queries? I do not know why SELECT @@ session.tx_isolation occurs and rollback. When I use a transaction, I get a commit and then rollback. Not sure why rollback is always connected to the cable.

Thank you so much!

My conf: Spring 2.5.6, Hibernate 3.6.0, Mysql 5.1

datasoure.xml:

<bean id="dataSource" destroy-method="close"
    class="org.apache.commons.dbcp.BasicDataSource">
    <property name="driverClassName" value="${jdbc.driverClassName}" />
    <property name="url" value="${jdbc.url}" />
    <property name="username" value="${jdbc.username}" />
    <property name="password" value="${jdbc.password}" />

    <property name="initialSize" value="3" />
    <property name="maxActive" value="20" />
    <property name="minIdle" value="3" />
    <property name="poolPreparedStatements" value="false" />
    <property name="defaultAutoCommit" value="false" />
    <property name="defaultTransactionIsolation" value="4" />
</bean>

Transaction Manager Definition:

<bean id="transactionManager"
    class="org.springframework.orm.hibernate3.HibernateTransactionManager">
    <property name="sessionFactory" ref="sessionFactory" />
</bean>

UPDATE.

<property name="defaultReadOnly" value="true" />

, ( , readOnly = false) db, SQLException. readonly true. , HibernateTemplate.

aspectj .

<aop:aspectj-autoproxy proxy-target-class="true" />
+5
1

. . Spring 2.5.x .

12/3/11: , , , , . @Transactional (readOnly = true), .

12/20/11: , . , , , . tx: , . . 10.5.1 Spring.

+1

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