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https://issues.apache.org/jira/browse/HIVE-27198?focusedWorklogId=859408&page=com.atlassian.jira.plugin.system.issuetabpanels:worklog-tabpanel#worklog-859408
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ASF GitHub Bot logged work on HIVE-27198:
-----------------------------------------

                Author: ASF GitHub Bot
            Created on: 27/Apr/23 13:12
            Start Date: 27/Apr/23 13:12
    Worklog Time Spent: 10m 
      Work Description: deniskuzZ commented on code in PR #4174:
URL: https://github.com/apache/hive/pull/4174#discussion_r1179137448


##########
standalone-metastore/metastore-server/src/main/java/org/apache/hadoop/hive/metastore/txn/CompactionTxnHandler.java:
##########
@@ -888,35 +887,13 @@ public void cleanEmptyAbortedAndCommittedTxns() throws 
MetaException {
           */
         long lowWaterMark = getOpenTxnTimeoutLowBoundaryTxnId(dbConn);
 
-        String s = "SELECT \"TXN_ID\" FROM \"TXNS\" WHERE " +
+        String s = "DELETE FROM \"TXNS\" WHERE " +

Review Comment:
   Could we move sql to constants (see `TxnQueries`) and use prepared statement?





Issue Time Tracking
-------------------

    Worklog Id:     (was: 859408)
    Time Spent: 1h 20m  (was: 1h 10m)

> Delete directly aborted transactions instead of select and loading ids
> ----------------------------------------------------------------------
>
>                 Key: HIVE-27198
>                 URL: https://issues.apache.org/jira/browse/HIVE-27198
>             Project: Hive
>          Issue Type: Improvement
>            Reporter: Mahesh Raju Somalaraju
>            Assignee: Mahesh Raju Somalaraju
>            Priority: Major
>              Labels: pull-request-available
>          Time Spent: 1h 20m
>  Remaining Estimate: 0h
>
> in cleaning the aborted transaction , we can directly deletes the txns 
> instead of selecting and process.
> method name: 
> cleanEmptyAbortedAndCommittedTxns
> Code:
> String s = "SELECT \"TXN_ID\" FROM \"TXNS\" WHERE " +
> "\"TXN_ID\" NOT IN (SELECT \"TC_TXNID\" FROM \"TXN_COMPONENTS\") AND " +
> " (\"TXN_STATE\" = " + TxnStatus.ABORTED + " OR \"TXN_STATE\" = " + 
> TxnStatus.COMMITTED + ") AND "
> + " \"TXN_ID\" < " + lowWaterMark;
>  
> proposed code:
> String s = "DELETE \"TXN_ID\" FROM \"TXNS\" WHERE " +
> "\"TXN_ID\" NOT IN (SELECT \"TC_TXNID\" FROM \"TXN_COMPONENTS\") AND " +
> " (\"TXN_STATE\" = " + TxnStatus.ABORTED + " OR \"TXN_STATE\" = " + 
> TxnStatus.COMMITTED + ") AND "
> + " \"TXN_ID\" < " + lowWaterMark;
>  
> the select needs to be eliminated and the delete should work with the where 
> clause instead of the built in clause
> we can see no reason for loading the ids into memory and then generate a huge 
> sql
>  
> Bathcing is also not necessary here, we can deletes the records directly



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