Re: counting related rows

James Cloos wrote:
> I have a table which includes a text column containing posix-style
> paths. Ie, matching the regexp "^[^/]+(/[^/]+)*$".
>
> I need to do a query of a number of columns from that table, plus the
> count of rows which are "children" of the current row.
>
> The query:
>
> SELECT count(*) AS nch FROM m WHERE o = (SELECT o FROM m WHERE id=30016)
> AND name ILIKE (SELECT name || '/%' FROM m WHERE id=30016);
>
> selects that extra column given the id.
>
> A view containing all of the columns from m plus a column matching the
> above select would cover my needs well.
>
> But I haven't been able to get the syntax right.

It would help if you provided:
a) statements to create sample data
b) expected results from sample data

Does this do what you want?

select * from m, (SELECT count(*) AS nch FROM m WHERE o = (SELECT o FROM
m WHERE id=30016) AND name ILIKE (SELECT name || '/%' FROM m WHERE
id=30016)) om;