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From John English <john.fore...@gmail.com>
Subject Re: Unique constraint, or something like it
Date Mon, 12 Mar 2012 12:06:16 GMT
On 11/03/2012 19:46, Jean-Yves Linet wrote:
> Can't you use 0 rather than 1 for "null" section.

Now that sequences have been added, I suppose so. It's a table which has
been around for a while and uses GENERATED ALWAYS AS IDENTITY, so there
is a row 1 anyway. Changing the table without breaking anything is going
to be interesting -- create a new table, insert a row 0, copy the old
table across, drop all the FK constraints in other tables, drop the old
table, rename the new one, recreate the FK constraints, not to mention
all the views and triggers... And fix the code to take 0 or null so it
will work before and after the changeover.

Oh well. Maintenance is always such fun.


  John English | My old University of Brighton home page is still here:
               | http://www.cem.brighton.ac.uk/staff/je/

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