On Mon, Feb 28, 2011 at 05:39:07PM -0500, Alan Acosta wrote: > But i have a new problem there, i have no rows for update, i create new rows > when the seats are sold, cause rarely the database knows the capacity of the > bus, number of seats, even some bus doesn't have seat number 4 for example > :p. So i cannot SELECT FOR UPDATE no existent rows, but i still need to lock > in some way in order to check if seat number X was already sold or is free ! Someone else suggests that you need a uniqueness constraint, and I agree. But I also don't understand how you can be ensuring not to double-sell something if you don't have the list of inventory prior to its being sold. A -- Andrew Sullivan ajs@xxxxxxxxxxxxxxx -- Sent via pgsql-general mailing list (pgsql-general@xxxxxxxxxxxxxx) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-general
