Auto update spaces left?

[BP123]

Hi, sorry for being a pest but I was wondering how I can do this.

Say I had a database and there was 40 spaces for football and i booked a member in for football how would i make the number of spaces left change from 40 to 39?

Thanks

 

[gemma-the-husky]

either have a field for the number of spaces left (or the number booked) and update the table with code like this

currentdb.execute "update sometable set spacesleft = spacesleft +1

but better still, don't store the number of spaces - just record the player - and then have a query to count the players whenever you need the total.