Re: row numbering

Hi!

thanks for your respose!

sorry if i was not very clear with my question...

On Wed, 10 May 2000, Peter Eisentraut wrote:

> Marcin Inkielman writes:
>
> > how may i easyly obtain row numbers in a query:
>
> In the SQL data model, rows don't have numbers, because rows aren't
> ordered -- a query may return the rows in any order. So if you are

sure, i know that

> building on that assumption you might have to rethink slightly.

>
> If you need to number your records for some reason, say invoice numbers,
> you can use a sequence:

that is exactly i want to obtain. i would like to have:

1 | first item
2 | second,
3 | ... and so on.

each time i do a select on a table and aways starting with a "1".

>
> create table my_tbl (
> nr serial, -- creates implicit sequence
> ... more fields ...
> );
>
> Then you can select them like any other field. You say you had
> unsatisfying results, would you care to explain why?

the main problem i have with sequences (or temporary tables - as i think
you suggest) is that i have multiples concurrent transactions at he same
time. as they are generated by a single cgi script, if i use a sequence it
will have the same name for each transaction, and therefore only the first
trasaction will work. of course i may lock it just like a simple table but
i am not sure this is a simpliest way. i am just searching something
simplier

>
> Lastly, there is the OID which every row gets automatically assigned by
> the system. This is a unique number across the whole installation. You can
> access it as
> select oid, your, fields, here from table ...
> like a regular column. The OID may be good enough to get some sort of
> number on a row but be aware that it is wildly non-portable.

i thought to use oids but i am no sure if it is possible to obtain the
result i require

>
>
>

Marcin Inkielman