Oracle FAQ | Your Portal to the Oracle Knowledge Grid |
Home -> Community -> Usenet -> c.d.o.misc -> Corrupt index in data mart?
Help, all oracle expert:
Symptom: performance of a query that join multiple tables (including a
very large fact table) used to take about 50secs to return data
(whatever the tools were used). The very large fact table was then
truncated one day. Then all the same data were reloaded into this fact
table. The indexes on this fact table were remained unchanged.
The same query then took more than 6 mins. The explain plan of the
query looked exactly the same as the one before, i.e., made use of all
the pre-defined indexes in the very large fact table. It looked that
the query used the correct plan but the indexes were not actually used
(or some problem here?).
Have tried to drop indexes and re-created again, but it's worst, i.e., even the plan did not use the correct indexes.
Any ideas? Received on Mon Oct 18 1999 - 07:49:31 CDT