[ADF-11.1.2] Locking issue with SQL 92

Question

I see one Locking issue with SQL92 Oracle ADF Application.
ADF Version: [ADF-11.1.2]
Database: Oracle 10g Express Edition
Situation 1:
With Following setting:
File: Application Resource > Description > ADF META-INF > adf-config.xml
    <startup>
      <amconfig-overrides>
        <config:Database jbo.SQLBuilder="SQL92" jbo.locking.mode="optimistic"/>
      </amconfig-overrides>
    </startup>I have a page showing record 'x' of view object. I open same record on another page. Now I have same record showing on two different tabs of browser.
1. I modify first record and save it. It worked... Got commited to database.
2. I goto second tab and modify same record and tried to same it. It throws me an error - Another user has changed the row with primary key oracle.jbo.Key[38 ] . As expected...
3. I then, reopen the same record on 3rd tab of browser. Modify it and tried to save it. It just hang... as if it is processing the record endlessly.
If I see the Log:
<BaseSQLBuilderImpl> <doEntitySelectForAltKey> [312] BaseSQLBuilderImpl Executing doEntitySelect ... (true)
<BaseSQLBuilderImpl> <doEntitySelectForAltKey> [313] Generating new LOCK statement
<BaseSQLBuilderImpl> <buildSelectString> [314] Built select: 'SELECT ID, CI_ID, COLUMN_NAME, DISPLAY_COLUMN_NAME, COLUMN_VALUE, CREATE_DATE, CREATE_BY FROM ESUSER.CI_AUDIT'
<BaseSQLBuilderImpl> <doEntitySelectForAltKey> [315] Executing LOCK "SELECT ID, CI_ID, COLUMN_NAME, DISPLAY_COLUMN_NAME, COLUMN_VALUE, CREATE_DATE, CREATE_BY FROM ESUSER.CI_AUDIT WHERE ID=? FOR UPDATE"
<BaseSQLBuilderImpl> <bindWhereAttrValue> [316] Where binding param 1: 38
That's it.. nothing happens further.. If I execute above query on SQL Worksheet, it doesn't come up with the result. Just hang for something...
SELECT ID, CI_ID, COLUMN_NAME, DISPLAY_COLUMN_NAME, COLUMN_VALUE, CREATE_DATE, CREATE_BY FROM ESUSER.CI_AUDIT WHERE ID='38' FOR UPDATE I can execute above query for other record of same table but not '38'. Even if I fire commit command to database, it is not working.
I have to restart the database services to bring everything to normal state.
Situation 2:
With Oracle as Database :
    <startup>
      <amconfig-overrides>
        <config:Database jbo.SQLBuilder="Oracle" jbo.locking.mode="optimistic"/>
      </amconfig-overrides>
    </startup>Everything is working file. i.e. at step 3, record is getting modified successfully with following log:
<OracleSQLBuilderImpl> <doEntitySelectForAltKey> [27] OracleSQLBuilder Executing doEntitySelect on: ESUSER.CI_AUDIT (true)
<ADFLogger> <begin> Entity read all attributes
<OracleSQLBuilderImpl> <buildSelectString> [28] Built select: 'SELECT ID, CI_ID, COLUMN_NAME, DISPLAY_COLUMN_NAME, COLUMN_VALUE, CREATE_DATE, CREATE_BY FROM ESUSER.CI_AUDIT CIAudit'
<OracleSQLBuilderImpl> <doEntitySelectForAltKey> [29] Executing LOCK...SELECT ID, CI_ID, COLUMN_NAME, DISPLAY_COLUMN_NAME, COLUMN_VALUE, CREATE_DATE, CREATE_BY FROM ESUSER.CI_AUDIT CIAudit WHERE ID=? FOR UPDATE NOWAIT
<ADFLogger> <addContextData> Entity read all attributes
<OracleSQLBuilderImpl> <bindWhereAttrValue> [30] Where binding param 1: 38
<ADFLogger> <addContextData> Entity read all attributes
<ADFLogger> <end> Entity read all attributes
<ADFLogger> <end> Lock Entity
<ADFLogger> <begin> Before posting the entity's changes
<ADFLogger> <begin> Updating audit columns
<ADFLogger> <end> Updating audit columns
<ADFLogger> <end> Before posting the entity's changes
<OracleSQLBuilderImpl> <doEntityDML> [31] OracleSQLBuilder Executing, Lock 2 DML on: ESUSER.CI_AUDIT (Update)
<OracleSQLBuilderImpl> <buildUpdateStatement> [32] UPDATE buf CIAudit>#u SQLStmtBufLen: 210, actual=60
<OracleSQLBuilderImpl> <doEntityDML> [33] UPDATE ESUSER.CI_AUDIT CIAudit SET COLUMN_VALUE=? WHERE ID=?
<ADFLogger> <begin> Entity DML
<OracleSQLBuilderImpl> <bindUpdateStatement> [34] Update binding param 1: cip7ri1
<OracleSQLBuilderImpl> <bindWhereAttrValue> [35] Where binding param 2: 38
<ADFLogger> <addContextData> Entity DML
<ADFLogger> <end> Entity DML
Can any one please tell me, what is the issue with SQL92 setting ?
Edited by: Anandsagar Sah on Mar 11, 2012 8:10 AM

Answer 1

The framework works correctly in the Situation #1. Please, note that the locking statement in this case is "SELECT ... FOR UPDATE", but not "SELECT ... FOR UPDATE NOWAIT" (as it is in the Situation #2). When you entered the 2nd tab and tried to update the row, then the framework executed the locking statement and the row was locked (and it remained locked because the framework detected that another user had modified the row, so it stopped the processing and no COMMIT operation was executed). When you entered the 3rd tab and tried to update the row, then the framework tried to lock the row againg, but the locking statement was blocked by the existign lock and it started waiting on the lock from the 2nd tab. So this is expected behaviour.
The interesting question is why you do not get any error in the Situation #2. In my opinion you should get an error because the locking statement from the 3rd tab should fail immediately (because the row should have been locked from the 2nd tab and the locking statement is with NOWAIT option). I suspect that when the DB is Oracle and you use Oracle SQLBuilder, then the ADF issues a DB savepoint at the beginning of the DML operation and rolls back to the savepoint is a case of some failure, so the 2nd tab has not left any lock. You can check this by setting on SQL trace on the DB server.
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