| From: | "Marc G(dot) Fournier" <scrappy(at)hub(dot)org> |
|---|---|
| To: | pgsql-hackers(at)postgresql(dot)org |
| Subject: | pg_stats explained ... ? |
| Date: | 2002-02-13 13:31:30 |
| Message-ID: | 20020213092905.A19107-100000@mail1.hub.org |
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| Lists: | pgsql-hackers |
Morning all ...
Can someone explain to me how I should read this:
tablename | attname | avg_width | n_distinct
-------------------------+----------------------------+-----------+------------
iwantu_pro_week | uid | 8 | -1
iwantu_pro_week | pro_week_agent | 9 | 9
iwantu_pro_week | pro_week_time | 8 | -0.976321
iwantu_pro_week | pro_week_post | 5 | 2
iwantu_pro_week | pro_week_club | 2 | 1
n_distinct, I'm taking it, of -1 means its a UNIQUE INDEX, and the
positive numbers are exact #'s ... but, -0.976321? :)
Also, how is the avg_width interpreted?
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