Thread: [GENERAL] Vaccum Query

[GENERAL] Vaccum Query

From

PAWAN SHARMA

Date:

04 May 2017, 15:04:43

Hi All,

Any Idea what happens when we run standard vacuum (without full) on a table which has exclusive lock (or alter statement is being processed on that table).

What happens in this case ? Will vacuum wait for the alter to commit ? If so, how long ? If not, then what ?

And what actions can be taken to prevent this ?

Thanks & Regards,
Pawan Sharma

+91-9899396940

Skpye ID: pawanshr.0963

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Re: [GENERAL] Vaccum Query

From

Vik Fearing

Date:

05 May 2017, 23:03:29

On 05/04/2017 02:04 PM, PAWAN SHARMA wrote:

Hi All,

Any Idea what happens when we run standard vacuum (without full) on a table which has exclusive lock (or alter statement is being processed on that table).
What happens in this case ? Will vacuum wait for the alter to commit ?

Yes.

If so, how long ?

Either forever or for however long lock_timeout and/or statement_timeout are set to (or any user command like Ctrl+C).

If not, then what ?

If any of those limits are reached, the vacuum is cancelled.

And what actions can be taken to prevent this ?

Prevent what? Even if the vacuum could run while the other transaction had the exclusive lock, it wouldn't be able to do any work.

-- 
Vik Fearing                                          +33 6 46 75 15 36
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