table fetch continued row can cause performance issues.
It has been seen (anecdotal evidence) that dropping and recreating Global Temporary Tables on a periodic basis can have positive performance improvements.
Additionally it has been proven that issuing REBUILDs on indexes to compact it and minimize fragmented space can help performance.
Recommendation:
Perform REBUILDs on indexes. After issuing a REBUILD on your indexes be sure to gather stats via the DBMS_STATS package.
Also consider reorganizing data via export/import to pack rows more tightly and alleviate chained row issues.
(FRAGMENTATION = POOR PERFORMANCE)
