Re: Why would this slow the query down so much?

Stuart Grimshaw <nospam@smgsystems.co.uk> writes:
> SELECT a.category, b.headline, b.added, c.friendlyname
> FROM caturljoin as a
>         INNER JOIN stories as b ON (a.url = b.source)
>         INNER JOIN urllist as c ON (a.url = d.urn)
> WHERE a.category = 93 ORDER BY b.added DESC LIMIT 1;

(I assume "d.urn" is a typo for "c.urn"...)

The query plan you show looks pretty reasonable if the planner's row
count estimates are in the right ballpark.  How many caturljoin rows
have category = 93?  How many stories rows will match each caturljoin
row?  How many urllist rows ditto?
        regards, tom lane