Re: Finding Max Value in a Row

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От Jasen Betts
Тема Re: Finding Max Value in a Row
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Msg-id jok24h$scd$1@reversiblemaps.ath.cx
обсуждение исходный текст
Ответ на Finding Max Value in a Row  (Carlos Mennens <carlos.mennens@gmail.com>)
Список pgsql-sql
On 2012-05-11, Carlos Mennens <carlos.mennens@gmail.com> wrote:
> I have a problem in SQL I don't know how to solve and while I'm sure
> there are 100+ ways to do this in ANSI SQL, I'm trying to find the
> most cleanest / efficient way. I have a table called 'users' and the
> field 'users_id' is listed as the PRIMARY KEY. I know I can use the
> COUNT function, then I know exactly how many records are listed but I
> don't know what the maximum or highest numeric value is so that I can
> use the next available # for a newly inserted record. Sadly the
> architect of this table didn't feel the need to create a sequence and
> I don't know how to find the highest value.

If you need pecisely the next value a sequence won't get you there anyway.



select max(id) from users;

that's only going to be reliable if you have a single concurent database user
doing inserts.



>
> Thank you for any assistance!
>


-- 
⚂⚃ 100% natural



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