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Optimization Hint - QUERYNO
- Thread starter MarcLodge
- Start date
On LUW we had a case for the following:
The problem was that the statistical information on selectivity is only available for the 3 most and 3 fewest values, not in between. And sometimes the access path can differ ...
The queryno you mention is related to the host?
Or you have any statement sample ?
We use it to specify the query number to later find the correct output in the Explain Table (not having a fully featured Visual Explain on z/OS available).
Same should be possible on LUW as well - so it is not a real optimization hint as such.
Juliane
The problem was that the statistical information on selectivity is only available for the 3 most and 3 fewest values, not in between. And sometimes the access path can differ ...
The queryno you mention is related to the host?
Or you have any statement sample ?
We use it to specify the query number to later find the correct output in the Explain Table (not having a fully featured Visual Explain on z/OS available).
Same should be possible on LUW as well - so it is not a real optimization hint as such.
Juliane
- Thread starter
- #3
Thanks for your response Julianne. It's not the facility that you describe, and it's not one I've come acroos before. It's something they are implementing at my current site, details of which can be found here:
I wondered if anybody had actually used it, and could give any comments.
Marc
I wondered if anybody had actually used it, and could give any comments.
Marc
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