> Merlin Moncure wrote:
>
> > I need a fast way (sql only preferred) to solve the following
problem:
> > I need the smallest integer that is greater than zero that is not in
the
> > column of a table.
> >
> > I've already worked out a query using generate_series (not scalable)
and
> > pl/pgsql. An SQL only solution would be preferred, am I missing
> > something obvious?
> Probably not, but I thought about this "brute-force" approach... :-)
> This should work well provided that:
>
> - you have a finite number of integers. Your column should have a
biggest
> integer value with a reasonable maximum like 100,000 or 1,000,000.
> #define YOUR_MAX 99999
[...]
:-) generate_series function does the same thing only a little bit
faster (although less portable).
generate_series(m,n) returns set of integers from m to n with time
complexity n - m. I use it for cases where I need to increment for
something, for example:
select now()::date + d from generate_series(0,355) as d;
returns days from today until 355 days from now.
Merlin
---------------------------(end of broadcast)---------------------------
TIP 2: you can get off all lists at once with the unregister command
(send "unregister YourEmailAddressHere" to [EMAIL PROTECTED])
