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Martin Smith
Martin Smith
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How does sampling work when updating statistics?

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Nick Chammas
Nick Chammas
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Sql Server Statistics - how How does sampling work?

I have (several)several massive tables. II'd like to ensure their statistics are up to date via a weekly maintenance plan.

However, doing so is taking too much time.

If I specify

WITH SAMPLE 50 PERCENT

WITH SAMPLE 50 PERCENT

does SqlSQL Server then sample:

a) the first 50% of pages b) every other page c) some other strategy

  1. the first 50% of pages
  2. every other page
  3. or some other strategy?

BOLBOL is not clear on this.

Many thanks.

Sql Server Statistics - how does sampling work?

I have (several) massive tables. I like to ensure their statistics are up to date via a weekly maintenance plan.

However, doing so is taking too much time.

If I specify

WITH SAMPLE 50 PERCENT

does Sql Server then sample

a) the first 50% of pages b) every other page c) some other strategy

BOL is not clear on this.

Many thanks.

How does sampling work?

I have several massive tables. I'd like to ensure their statistics are up to date via a weekly maintenance plan.

However, doing so is taking too much time.

If I specify

WITH SAMPLE 50 PERCENT

does SQL Server then sample:

  1. the first 50% of pages
  2. every other page
  3. or some other strategy?

BOL is not clear on this.

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Nik
Nik
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Sql Server Statistics - how does sampling work?

I have (several) massive tables. I like to ensure their statistics are up to date via a weekly maintenance plan.

However, doing so is taking too much time.

If I specify

WITH SAMPLE 50 PERCENT

does Sql Server then sample

a) the first 50% of pages b) every other page c) some other strategy

BOL is not clear on this.

Many thanks.