log file is big. But I guess it is no problem for your experts.
When I query informix, 243 and 101 error will show up. And if I use informix client to execute the following query (please refer to segment log), it's ok.


Apr 16 18:01:29-Thread 158c-Project TaskManager/initial: Component TMQuery: Executing SQL

Apr 16 18:01:29-Thread 158c-Project TaskManager/initial: Component TMQuery: select vtoid,bpState,overflow,bpTimer,bpTimerOverflow,bpV ersion,bpControlState,numTransitions,timeEntered,t imeCreated,info$,info$model,info$activity,info$per former$,info$performer$type,info$performer$name,in fo$performer$privInfo,info$priority,info$reassigna ble,info$rejectable,info$startDate,info$dueDate,in fo$detailLink,info$supervisorLink,info$cost,info$l abel,performer,activity$,activity$oid,activity$ind ex,referenceData,description from task where vtoid=TID4:7009:/Projects/TaskManager/initial

Apr 16 18:01:30-Thread 158c-Project TaskManager/initial: Component TMQuery: SQL exception with error code -243, SQL state: IX000 and message: Could not position within a table (informix.task)..

Apr 16 18:01:30-Thread 158c-Project TaskManager/initial: Component TMQuery: SQL exception with error code -101, SQL state: IX000 and message: ISAM error: file is not open..

Apr 16 18:01:30-Thread 158c-Project TaskManager/initial: Component TMQuery: The statement that causes error is 'select vtoid,bpState,overflow,bpTimer,bpTimerOverflow,bpV ersion,bpControlState,numTransitions,timeEntered,t imeCreated,info$,info$model,info$activity,info$per former$,info$performer$type,info$performer$name,in fo$performer$privInfo,info$priority,info$reassigna ble,info$rejectable,info$startDate,info$dueDate,in fo$detailLink,info$supervisorLink,info$cost,info$l abel,performer,activity$,activity$oid,activity$ind ex,referenceData,description from task where vtoid=?'.

Apr 16 18:01:30-Thread 158c-Project TaskManager/initial: Component TMQuery: Failed to load object from table 'Task' with id 'TID4:7009:/Projects/TaskManager/initial'.

Apr 16 18:01:30-Thread 158c-Project TaskManager/initial: Component TMQuery: SQL exception with error code -243, SQL state: IX000 and message: Could not position within a table (informix.task)..

Apr 16 18:01:30-Thread 158c-Project TaskManager/initial: Component TMQuery: SQL exception with error code -101, SQL state: IX000 and message: ISAM error: file is not open..

java.sql.SQLException: Could not position within a table (informix.task).
com.informix.jdbc.IfxSqli.addException(IfxSqli.jav a:3082)
com.informix.jdbc.IfxSqli.receiveError(IfxSqli.jav a:3396)
com.informix.jdbc.IfxSqli.dispatchMsg(IfxSqli.java :2259)
com.informix.jdbcx.IfxXASqli.receiveMessage(IfxXAS qli.java:119)
com.informix.jdbc.IfxSqli.sendStatementQuery(IfxSq li.java:1444)
com.informix.jdbc.IfxSqli.executeStatementQuery(If xSqli.java:1383)
com.informix.jdbc.IfxSqli.executeStatementQuery(If xSqli.java:1313)
com.informix.jdbc.IfxResultSet.executeQuery(IfxRes ultSet.java:216)
com.informix.jdbc.IfxStatement.executeQueryImpl(If xStatement.java:839)
com.informix.jdbc.IfxPreparedStatement.executeQuer y(IfxPreparedStatement.java:246)
...
...

lock mode row can resolve this problem.