Re: No result when selecting attstattarget from pg_attribute

On Thu, 2019-11-28 at 09:55 +0000, William Sescu (Suva) wrote:
> Now I create the custom statistics, however, attstattarget is still -1
>
> (klb(at)[local]:55000)[knowledgebase]> CREATE STATISTICS s1 (dependencies) ON a, b FROM t1;
> CREATE STATISTICS
>
> (klb(at)[local]:55000)[knowledgebase]> select attrelid::regclass as name, attname, attstattarget from pg_attribute where attname in ('a','b');
> name | attname | attstattarget
> ------+---------+---------------
> t1 | a | -1
> t1 | b | -1
> (2 rows)
>
> Am I looking at the wrong view? I am planning to do some upgrades to 12.x, and therefore, I created this little test case
> to make sure that I don't forget to set custom statistics on the new version, if there are any.

"attstattarget" is set to a value different from -1 if you define a special
statistics detail level for the column:

ALTER TABLE t1 ALTER a SET STATISTICS 1000;

It has nothing to do with extended statistics.

Yours,
Laurenz Albe
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