[SOLR-2045] DIH doesn't release jdbc connections in conjunction with DB2

• Type: Bug
• Status: Closed
• Priority: Major
• Resolution: Fixed
• Affects Version/s: 1.4.1, 3.6, 4.0
• Fix Version/s: 4.1, 6.0
• Component/s: contrib - DataImportHandler

Environment

DB2 SQLLIB 9.5, 9.7 jdbc Driver

• Assignee: James Dyer
• Reporter: Fenlor Sebastia
• Created: 14/Aug/10 00:03
• Updated: 09/May/16 18:56
• Resolved: 12/Nov/12 17:45

Description

Using the JDBCDatasource in conjunction with the DB2 JDBC Drivers results in the following error when the DIH tries to close the the connection due to active transactions. As a consequence each delta im port or full import opens a new connection without closing it. So the maximum amount of connections will be reached soon. Setting the connection to readOnly or changing the transaction isolation level doesn't help neither.

The JDBC Driver I used: "com.ibm.db2.jcc.DB2Driver" relieing in db2jcc4.jar shipped with DB2 Express 9.7 for example

Here is the stack trace...

14.08.2010 01:49:51 org.apache.solr.handler.dataimport.JdbcDataSource closeConnection
FATAL: Ignoring Error when closing connection
com.ibm.db2.jcc.am.SqlException: [jcc][10251][10308][4.8.87] java.sql.Connection.close() requested while a transaction is in progress on the connection.The transaction remains active, and the connection cannot be closed. ERRORCODE=-4471, SQLSTATE=null
at com.ibm.db2.jcc.am.gd.a(gd.java:660)
at com.ibm.db2.jcc.am.gd.a(gd.java:60)
at com.ibm.db2.jcc.am.gd.a(gd.java:120)
at com.ibm.db2.jcc.am.lb.u(lb.java:1202)
at com.ibm.db2.jcc.am.lb.x(lb.java:1225)
at com.ibm.db2.jcc.am.lb.v(lb.java:1211)
at com.ibm.db2.jcc.am.lb.close(lb.java:1195)
at com.ibm.db2.jcc.uw.UWConnection.close(UWConnection.java:838)
at org.apache.solr.handler.dataimport.JdbcDataSource.closeConnection(JdbcDataSource.java:399)
at org.apache.solr.handler.dataimport.JdbcDataSource.close(JdbcDataSource.java:390)
at org.apache.solr.handler.dataimport.DataConfig$Entity.clearCache(DataConfig.java:173)
at org.apache.solr.handler.dataimport.DataConfig.clearCaches(DataConfig.java:331)
at org.apache.solr.handler.dataimport.DataImporter.doFullImport(DataImporter.java:339)
at org.apache.solr.handler.dataimport.DataImporter.runCmd(DataImporter.java:389)
at org.apache.solr.handler.dataimport.DataImporter$1.run(DataImporter.java:370)

Well the issue can be solved by invoking a commit or rollback directly before the connection.close() statement. Here is the code snipped of changes I made in JdbcDatasource.java

private void closeConnection() {
try {
if (conn != null) {

if (conn.isReadOnly())

{ LOG.info("connection is readonly, therefore rollback"); conn.rollback(); }

else

{ LOG.info("connection is not readonly, therefore commit"); conn.commit(); }

conn.close();
}
} catch (Exception e)

{ LOG.error("Ignoring Error when closing connection", e); }

}

Issue Links

• is related to: SOLR-3856 DIH: Better tests for SqlEntityProcessor