MERGE using DECODE logic to control UPDATE The SQL below has been running extremely well for over a years in our Production application on Oracle release 10.1. We have recently upgraded to Oracle release 11.1 and this same SQL routine now takes a minimum of 4 times longer to run on 11.1 Has anyone else encountered such performance degradation when moving from 10.1 to 11.1. It appears to be limited to this particular routine as 99.9% of the rest of our application seems to run faster on Oracle 11.1. Any ideas or similar experiences out there ? SET NEWPAGE 0 SET SPACE 0 SET LINESIZE 79 SET PAGESIZE 0 SET ECHO OFF SET FEEDBACK OFF SET HEADING OFF SET TERM OFF SPOOL /mbshist/mbsload/cmo_dir/logs/updt_endrange.sqlrpt MERGE INTO mbs_daterange md USING ( SELECT * FROM cmo_keyvals ) ck ON (md.seqno = ck.seqno AND md.item = ck.item) WHEN MATCHED THEN UPDATE SET md.end_range = DECODE(SIGN(ck.end_range-md.end_range),1,ck.end_range,md.end_range), md.begin_range = DECODE(SIGN(ck.end_range-md.begin_range),-1,ck.end_range,md.begin_range) WHERE ck.end_range > md.end_range or ck.end_range < md.begin_range WHEN NOT MATCHED THEN INSERT (md.seqno, md.item, md.begin_range, md.end_range, md.location) VALUES (ck.seqno, ck.item, ck.end_range, ck.end_range, NULL); commit; SPOOL OFF quit; /

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