Re: Test to see if currval will fail?

On Fri, 2002-12-06 at 13:18, Kelly McDonald wrote:
> Josh,
>
> Actually, I'm not really concerned about what the last value was or is,
> but I am trying to find out if nextval has already been called within
> the current session. so I can do something like:
>
> if currval_wont_puke('sequence') then
>    select currval('sequence')
> else
>    select nextval('sequence')
>
> the part that I'm looking for is the currval_wont_puke() function.

Since it is in the _current_ session, surely you can know whether you
have called nextval() without asking the backend?  You need to set a
flag in your program when you use it or do an insert that will trigger
it from a serial column, and test that.

--
Oliver Elphick                                Oliver.Elphick@lfix.co.uk
Isle of Wight, UK                             http://www.lfix.co.uk/oliver
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