[erlang-questions] Mnesia record count
Tue Nov 27 00:34:24 CET 2007
On Mon, Nov 26, 2007 at 11:47:44PM +0100, Maarten Engelen wrote:
> Currently I'm building an application that needs to do a lot of record
> checking by counting the number of records in a mnesia table based on
> some condition. Mnesia has been a live saver in the development of
> this application, but I can't find a decent solution to the mnesia
> equivalent of COUNT(*) in SQL. I haven't been able to check the number
> of records a certain query would return without reading the complete
> set of results into a list and getting the length of the list.
> I have been looking into the dirty_update_counter function, but this
> doesn't guarantee anything when I have multiple mnesia nodes.
> Any ideas?
How about mnesia:table_info(Table,size) ?
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