Re: How to auto-increment?

In response to Andre Lopes :
> Hi,
>  
> I have a table like this:
>  
> id_product
> id_increment
>  
> and I need to increment values in id_increment like this
>  
> prod_1
> 1
>  
> prod_1
> 2
>  
> prod_1
> 3
>  
> prod_2
> 1
>  

Ahh, you want to count per group, yes? Do you have 8.4? If yes, i would
suggest you an other way: use a CTE-query to count that. Or create a view
based on a CTE-query.

In your case:

select id_product, row_number() over (partition by id_product) from table

> Wich is the best way to do this? Using a trigger? Where can I find examples of
> plpgsql doing this?

With a TRIGGER there are possible, but what happens if you delete the
first record containing 'prod_1'?

> Sorry for my bad english.

Mee too ...

Andreas
--
Andreas Kretschmer
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