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index range scan vs index skip scan

edited May 15, 2019 4:10AM in SQL Performance (MOSC) 4 commentsAnswered

Hi

I am seeing different cost for a single SQL_ID. Cost is high when optimizer is doing index skip scan, while cost reduced to 4 times with index range scan.

Could someone brief about this phenomenon. And, if skip scan is expensive, can we have optimizer use better one instead?

We have autostats job enabled and I reviewed the histograms and they do not look stale, so as the stats.

Thanks

Siraj

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