HI,

I had one delete statement, it was running for some time, caused
fragmentation on indexes. The delete performance is getting worse.
After  reorg the indexes, the performance is getting better.

My question is I got explain before the reorg/runstats and after reorg/
runstats. The estimated costs are exactly the same..

I suppose the explain costs should be lower after reorg/runstats.

I don't understand this.

any suggestion is appreciated.

Thanks.