Mailing-List: contact derby-dev-help@db.apache.org; run by ezmlm
Precedence: bulk
Reply-To: <derby-dev@db.apache.org>
Message-ID: <28496522.1153720574802.JavaMail.jira@brutus>
Date: Sun, 23 Jul 2006 22:56:14 -0700 (PDT)
From: "Yip Ng (JIRA)" <derby-dev@db.apache.org>
To: derby-dev@db.apache.org
Subject: [jira] Updated: (DERBY-939) NullPointerException at
 ResultSet.close() time for simple query using UNION and INTERSECT
In-Reply-To: <724490560.1139591397506.JavaMail.jira@ajax.apache.org>
MIME-Version: 1.0
Content-Type: text/plain; charset=utf-8
Content-Transfer-Encoding: 7bit

     [ http://issues.apache.org/jira/browse/DERBY-939?page=all ]

Yip Ng updated DERBY-939:
-------------------------

    Attachment: derby939trunkdiffpatch1.txt
                derby939trunkstatpatch1.txt

Here is the patch for DERBY-939.  

The attached file derby939trunkdiffpatch1.txt contains the fix for this issue + testcases and is diffed against the trunk codeline and derby939trunkstatpatch1.txt contains the list of file changes.  I have ran derbyall suite and no new regression is introduced by this patch.  

As noted from my previous comment, the NPE is caused by a missing implementation of the runtime statistics for SetOpResultSet; thus, I implemented a class called RealSetOpResultSetStatistics under org.apache.derby.impl.sql.execute.rts package where all the runtime statistics classes reside and modified SetOpResultSet to process the runtime statistics attributes that RealSetOpResultSetStatistics need to address this issue.  

I verified the output of the testcases plan and they do not output null string or throw NPE anymore.  i.e.: 

SELECT i FROM t1 UNION SELECT j FROM t2 INTERSECT SELECT k FROM t3;

would have the following plan structure according to the plan output.  (See setOpPlan.sql for more details).

           SORT ( no dups )
                |
          UNION
              /     \
             /       \
    TSCAN   INTERSECT
          |                 /   \
         t1               /     \
                   SORT  SORT
                         |            |
                  TSCAN  TSCAN
                         |            |
                        t2          t3

Here is the release note if it makes it in 10.2:

==========================================================

Release Note for DERBY-939
----------------------------------------

PROBLEM

   Unable to produce query plan or runtime statistics for INTERSECT or EXCEPT operation when runtime statistics is enabled or when the property derby.language.logQueryPlan is set to true.
    
SYMPTOMS

   (1) A NUllPointerException(NPE) occurs when a SQL query is executed that involves a UNION and INTERSECT/EXCEPT operation in: 
          a) when the property derby.language.logQueryPlan=true OR 
          b) runtime statistics mode via a CALL SYSCS_UTIL.SYSCS_SET_RUNTIMESTATISTICS(1)  

       i.e.:

       Case a:  

       java -Dderby.language.logQueryPlan=true org.apache.derby.tools.ij
       
       ij> connect 'jdbc:derby:db1;create=true';
       create table t1 (i int);
       create table t2 (j int);
       create table t3 (a int);

       ij> select i from t1 union (select j from t2 intersect select a from t3);
       1
       -----------

       0 rows selected
       ERROR XJ001: Java exception: ': java.lang.NullPointerException'. 


       Case b:

       CALL SYSCS_UTIL.SYSCS_SET_RUNTIMESTATISTICS(1);
       SELECT i FROM t1 UNION SELECT j FROM t2 INTERSECT SELECT a FROM t3;
       1
       -----------

       0 rows selected
       ij> VALUES SYSCS_UTIL.SYSCS_GET_RUNTIMESTATISTIC();
       1
       --------------------------------------------------------------------------------
       ------------------------------------------------
       ERROR 38000: The exception 'java.lang.NullPointerException' was thrown while evaluating an expression.
       ERROR XJ001: Java exception: ': java.lang.NullPointerException'. 


   (2) When a query only contains a simple INTERSECT or EXCEPT operation and   
         the property derby.language.logQueryPlan=true., Derby outputs a null string in 
        derby.log instead of the actual execution plan in textual representation.

       i.e.:
       java -Dderby.language.logQueryPlan=true org.apache.derby.tools.ij

       ij> connect 'jdbc:derby:db1';        
       ij> SELECT i FROM t1 INTERSECT SELECT j FROM t2;
       ij> quit;

       In derby.log:
       
       2006-07-24 05:12:57.578 GMT Thread[main,5,main] (XID =186), (SESSIONID = 0), select i from t1 intersect select j from t2 ******* null

CAUSE

   Derby's INTERCEPT and EXCEPT runtime statistics are not implemented; 
   therefore, resulting in the stated problem above.The affected version is Derby 
   10.1.          

SOLUTION
    
   A fix to resolve the Derby symptom is available in 10.2? builds. 

WORKAROUND

   None.

==========================================================

I would appreciate it if someone can review this patch.  Thanks!


> NullPointerException at ResultSet.close() time for simple query using UNION and INTERSECT
> -----------------------------------------------------------------------------------------
>
>                 Key: DERBY-939
>                 URL: http://issues.apache.org/jira/browse/DERBY-939
>             Project: Derby
>          Issue Type: Bug
>          Components: SQL
>    Affects Versions: 10.2.0.0, 10.1.3.0
>         Environment: Embedded and server modes, with derby.language.logQueryPlan=true
>            Reporter: A B
>         Assigned To: Yip Ng
>            Priority: Minor
>         Attachments: derby939trunkdiffpatch1.txt, derby939trunkstatpatch1.txt
>
>
> If I set "derby.language.logQueryPlan" to true and then attempt to execute the following simple query using UNION and INTERSECT, Derby will return the correct results and then, _after_ returning the results, will throw a NullPointerException.  This error also occurs for 10.1.
> To reproduce:
> > java -Dderby.language.logQueryPlan=true org.apache.derby.tools.ij
> and then do:
> create table t1 (i int);
> create table t2 (j int);
> create table t3 (a int);
> ij> select i from t1 union (select j from t2 intersect select a from t3);
> 1
> -----------
> 0 rows selected
> ERROR XJ001: Java exception: ': java.lang.NullPointerException'.
> If I add data, the query will return the correct results,  but then throw the NPE.
> insert into t1 values 1, 2, 3, 4, 5;
> insert into t2 values 2, 4, 6, 8, 10;
> insert into t3 values 2, 3, 4;
> ij> select i from t1 union (select j from t2 intersect select a from t3);
> 1
> -----------
> 1
> 2
> 3
> 4
> 5
> 5 rows selected
> ERROR XJ001: Java exception: ': java.lang.NullPointerException'.
> The embedded and client stack traces are shown below. Both suggest that the problem occurs during the close of the result set.
> -- Embedded --
> java.lang.NullPointerException
> 	at org.apache.derby.impl.sql.execute.rts.RealUnionResultSetStatistics.getStatementExecutionPlanText(RealUnionResultSetStatistics.java:107)
> 	at org.apache.derby.impl.sql.execute.rts.RealSortStatistics.getStatementExecutionPlanText(RealSortStatistics.java:124)
> 	at org.apache.derby.impl.sql.execute.rts.RunTimeStatisticsImpl.getStatementExecutionPlanText(RunTimeStatisticsImpl.java:293)
> 	at org.apache.derby.impl.sql.execute.BasicNoPutResultSetImpl.finishAndRTS(BasicNoPutResultSetImpl.java:633)
> 	at org.apache.derby.impl.sql.execute.SortResultSet.finish(SortResultSet.java:479)
> 	at org.apache.derby.impl.jdbc.EmbedResultSet.close(EmbedResultSet.java:533)
> 	at org.apache.derby.tools.JDBCDisplayUtil.indent_DisplayResults(JDBCDisplayUtil.java:272)
> 	at org.apache.derby.tools.JDBCDisplayUtil.DisplayResults(JDBCDisplayUtil.java:260)
> 	at org.apache.derby.impl.tools.ij.utilMain.displayResult(utilMain.java:381)
> 	at org.apache.derby.impl.tools.ij.utilMain.doCatch(utilMain.java:434)
> 	at org.apache.derby.impl.tools.ij.utilMain.go(utilMain.java:310)
> 	at org.apache.derby.impl.tools.ij.Main.go(Main.java:203)
> 	at org.apache.derby.impl.tools.ij.Main.mainCore(Main.java:169)
> 	at org.apache.derby.impl.tools.ij.Main14.main(Main14.java:55)
> 	at org.apache.derby.tools.ij.main(ij.java:60)
> -- Client --
> ERROR (no SQLState): actual code point, 4692 does not match expected code point, 9224
> java.sql.SQLException: actual code point, 4692 does not match expected code point, 9224
>         at org.apache.derby.client.am.SqlException.getSQLException(SqlException.java:280)
>         at org.apache.derby.client.am.ResultSet.close(ResultSet.java:412)
>         at org.apache.derby.tools.JDBCDisplayUtil.indent_DisplayResults(JDBCDisplayUtil.java:272)
>         at org.apache.derby.tools.JDBCDisplayUtil.DisplayResults(JDBCDisplayUtil.java:260)
>         at org.apache.derby.impl.tools.ij.utilMain.displayResult(utilMain.java:381)
>         at org.apache.derby.impl.tools.ij.utilMain.doCatch(utilMain.java:434)
>         at org.apache.derby.impl.tools.ij.utilMain.go(utilMain.java:310)
>         at org.apache.derby.impl.tools.ij.Main.go(Main.java:203)
>         at org.apache.derby.impl.tools.ij.Main.mainCore(Main.java:169)
>         at org.apache.derby.impl.tools.ij.Main14.main(Main14.java:55)
>         at org.apache.derby.tools.ij.main(ij.java:60)
> Caused by: org.apache.derby.client.am.DisconnectException: actual code point, 4692 does not match ex
> pected code point, 9224
>         at org.apache.derby.client.net.Reply.zThrowSyntaxError(Reply.java:1157)
>         at org.apache.derby.client.net.Reply.parseLengthAndMatchCodePoint(Reply.java:1057)
>         at org.apache.derby.client.net.NetConnectionReply.parseSQLCARD(NetConnectionReply.java:2519)
>         at org.apache.derby.client.net.NetConnectionReply.parseRDBCMMreply(NetConnectionReply.java:2
> 00)
>         at org.apache.derby.client.net.NetConnectionReply.readLocalCommit(NetConnectionReply.java:13
> 3)
>         at org.apache.derby.client.net.ConnectionReply.readLocalCommit(ConnectionReply.java:42)
>         at org.apache.derby.client.net.NetConnection.readLocalCommit_(NetConnection.java:1347)
>         at org.apache.derby.client.am.Connection.readCommit(Connection.java:624)
>         at org.apache.derby.client.am.Connection.readAutoCommit(Connection.java:614)
>         at org.apache.derby.client.am.ResultSet.readAutoCommitIfNotAutoCommitted(ResultSet.java:509)
>         at org.apache.derby.client.am.ResultSet.readCloseAndAutoCommit(ResultSet.java:474)
>         at org.apache.derby.client.am.ResultSet.flowCloseAndAutoCommitIfNotAutoCommitted(ResultSet.j
> ava:455)
>         at org.apache.derby.client.am.ResultSet.closeX(ResultSet.java:425)
>         at org.apache.derby.client.am.ResultSet.close(ResultSet.java:407)
> ERROR XJ001: DERBY SQL error: SQLCODE: -1, SQLSTATE: XJ001, SQLERRMC: java.lang.NullPointerException
> [XX] XJ001.U
> java.sql.SQLException: DERBY SQL error: SQLCODE: -1, SQLSTATE: XJ001, SQLERRMC: java.lang.NullPointerException[XX]XJ001.U
>         at org.apache.derby.client.am.SqlException.getSQLException(SqlException.java:280)
>         at org.apache.derby.client.am.SqlException.getSQLException(SqlException.java:295)
>         at org.apache.derby.client.am.ResultSet.close(ResultSet.java:412)
>         at org.apache.derby.tools.JDBCDisplayUtil.indent_DisplayResults(JDBCDisplayUtil.java:272)
>         at org.apache.derby.tools.JDBCDisplayUtil.DisplayResults(JDBCDisplayUtil.java:260)
>         at org.apache.derby.impl.tools.ij.utilMain.displayResult(utilMain.java:381)
>         at org.apache.derby.impl.tools.ij.utilMain.doCatch(utilMain.java:434)
>         at org.apache.derby.impl.tools.ij.utilMain.go(utilMain.java:310)
>         at org.apache.derby.impl.tools.ij.Main.go(Main.java:203)
>         at org.apache.derby.impl.tools.ij.Main.mainCore(Main.java:169)
>         at org.apache.derby.impl.tools.ij.Main14.main(Main14.java:55)
>         at org.apache.derby.tools.ij.main(ij.java:60)

-- 
This message is automatically generated by JIRA.
-
If you think it was sent incorrectly contact one of the administrators: http://issues.apache.org/jira/secure/Administrators.jspa
-
For more information on JIRA, see: http://www.atlassian.com/software/jira