There is a blog posting that lists the recommendations for collecting statistics.
It makes these recommendations for indexed columns:
Collect Full Statistics
- Non-indexed columns used in predicates
- All NUSIs
- USIs/UPIs if used in non-equality predicates (range constraints)
- Most NUPIs (see below for a fuller discussion of NUPI statistic collection)
Can Rely on Random AMP Sampling
- USIs or UPIs if only used with equality predicates
- NUSIs with an even distribution of values
- NUPIs that display even distribution, and if used for joining, conform to assumed uniqueness
Those recommendations are the same no matter what statistics USING clauses you attach to the statistic when you are collecting it. I can't think of any difference between and indexed column and a non-indexed column when it comes to which USING options to apply, or how to apply them.
Raja,
There is a blog posting that lists the recommendations for collecting statistics.
It makes these recommendations for indexed columns:
Collect Full Statistics
- Non-indexed columns used in predicates
- All NUSIs
- USIs/UPIs if used in non-equality predicates (range constraints)
- Most NUPIs (see below for a fuller discussion of NUPI statistic collection)
Can Rely on Random AMP Sampling
- USIs or UPIs if only used with equality predicates
- NUSIs with an even distribution of values
- NUPIs that display even distribution, and if used for joining, conform to assumed uniqueness
Those recommendations are the same no matter what statistics USING clauses you attach to the statistic when you are collecting it. I can't think of any difference between and indexed column and a non-indexed column when it comes to which USING options to apply, or how to apply them.
Thanks, -Carrie