[hibernate-issues] [Hibernate-JIRA] Resolved: (HHH-2734) PreparedStatement leak with lazy properties

PreparedStatement leak with lazy properties ------------------------------------------- Key: HHH-2734 URL: http://opensource.atlassian.com/projects/hibernate/browse/HHH-2734 Project: Hibernate3 Issue Type: Bug Components: core Affects Versions: 3.2.4 Environment: Hibernate 3.2.4 Oracle 10g Sun Java 1.5.0 Reporter: Christian Gruber Assignee: Gail Badner Priority: Critical Hello! When iterating through more than 300 elements that have lazy properties, I get an ORA-01000 JDBC error ("maximum open cursors exceeded"). I found out that the root cause for this are unclosed prepared statements in AbstractBatcher.prepareSelectStatement(String). When I add the generated prepared statement to the statementsToClose set in this method, the problem vanishes. But I don't have an idea what other effects this might have, and why the prepared statement was not added to the statements to close in the first place. How to reproduce: - Make a class with at least one lazy property; instrument the byte code - Create an Oracle database with at least 300 entries in the table for this class - Execute the following code: Iterator<MyClass> it = session.createQuery("from MyClass mc").iterate(); while (it.hasNext()) { MyClass mc = it.next(); String la = mc.getLazyAttribute(); session.evict(mc); } - Watch the log for org.hibernate.jdbc.AbstractBatcher entries containing "about to open ResultSet" and see the numbers increase As already mentioned, a simple fix for this is adding "statementsToClose.add( ps );" into AbstractBatcher.java, around line 133 (assigning the PreparedStatement to a new variable "ps" first, of course), but as I don't understand the differences between the various PreparedStatement generating methods there, that might give rise to other problems. Thanks for looking at it, Christian