[TRAFODION-3092] Incorrect rowcount reported after commit conflict error

• Type: Bug
• Status: Closed
• Priority: Major
• Resolution: Fixed
• Fix Version/s: 2.3
• Component/s: sql-exe
• Assignee: Sandhya Sundaresan
• Reporter: Sandhya Sundaresan
• Created: 30/May/18 18:51
• Updated: 05/Sep/18 21:41
• Resolved: 20/Jun/18 03:18

Description

When there are 2 sessions doing concurrent SQL IUD operations like update or insert, a commit conflict can occur. When this error occurs, the rowcount reposrted by the SQL diagnostics is incorrect. Even though 0 rows got inserted, it reports 2 rows. Same for updates. 

 

>>insert into tl values (5,5),(6,6);
..

Breakpoint 3, BEGINTX (pp_tag=0x7ffff7e75c58, pv_timeout=-1, pv_type_flags=1)
at tmlib.cpp:923
923 TM_Transaction *lp_trans = NULL;
(gdb) c
Continuing.

Breakpoint 5, ExTransaction::commitTransaction (this=0x7ffff7e75b80, waited=0)
at ../executor/ex_transaction.cpp:645
645 dp2Xns_ = FALSE;
(gdb) c
Continuing.

Breakpoint 6, ComDiagsArea::insertNewError (this=0x7ffff7e98048)
at ../export/ComDiags.cpp:2756
2756 errors_.insert(newCondition_);
(gdb) c
Continuing.

Breakpoint 6, ComDiagsArea::insertNewError (this=0x7ffff7ef4408)
at ../export/ComDiags.cpp:2756
2756 errors_.insert(newCondition_);
(gdb) c
Continuing.

• • • ERROR[8616] A conflict was detected during commit processing. Transaction has been aborted. Detail :org.trafodion.dtm.TransactionManagerException: org.apache.hadoop.hbase.coprocessor.transactional.CommitConflictException: java.io.IOException: This Transaction [[transactionId: 257 regionTX: false status: PENDING neverReadOnly: false scan Size: 4 write Size: 2 startSQ: 9 prepareEditSize: 0 endEditSize: 0 editSize: 2]] has a scan, scanRange[startRow: \x80\x00\x00\x05, endRow: \x80\x00\x00\x05] that conflicts with a committed Transaction [[transactionId: 258 regionTX: false status: COMMITED neverReadOnly: false scan Size: 4 write Size: 2 startSQ: 9 prepareEditSize: 2 endEditSize: 1 editSize: 2 commitedSQ:9]] which , inserted a row with key[\x80\x00\x00\x05], in the region [TRAFODION.SEABASE.TL,,1527701720547.2d9b1459c2f326be937f14e414cc68ad.]
      org.trafodion.dtm.HBaseTxClient.prepareCommit(HBaseTxClient.java:525)

— 2 row(s) inserted.
>>