Re: How to use an alias name in the current select

Hello Dimitri,

Many thanks for your answers

Regards
Guy

Le 24/03/10 20:09, Dimitri Fontaine a écrit :
> Hi,
>
> Guy Deleeuw<G(dot)De_Leeuw(at)eurofer(dot)be> writes:
>
>> SELECT
>> t_orders_articles.k_id AS k_id
>> ,t_orders_articles.quantity AS order_qty
>> ,(SELECT sum(quantity) FROM t_deliveries_articles WHERE article_id =
>> t_orders_articles.k_id) AS delivery_qty
>> , (t_orders_articles.quantity - delivery_qty) AS qty
>> FROM t_orders_articles
>> ......;
>>
>> How can I make that without having 2 select call ?
>>
> Put it as a relation in a subquery, or use WITH if using 8.4.
>
> SELECT k_id, order_qty, quantity, delivery_qty,
> quantity - delivery_qty as qty
> FROM (
> SELECT
> t_orders_articles.k_id AS k_id
> ,t_orders_articles.quantity AS order_qty
> ,(SELECT sum(quantity) FROM t_deliveries_articles WHERE article_id =
> t_orders_articles.k_id) AS delivery_qty
> , t_orders_articles.quantity
> FROM t_orders_articles
> ) as t;
>
>
> Or
>
> WITH t AS (
> SELECT
> t_orders_articles.k_id AS k_id
> ,t_orders_articles.quantity AS order_qty
> ,(SELECT sum(quantity) FROM t_deliveries_articles WHERE article_id =
> t_orders_articles.k_id) AS delivery_qty
> , t_orders_articles.quantity
> FROM t_orders_articles
> )
> SELECT k_id, order_qty, quantity, delivery_qty,
> quantity - delivery_qty as qty
> FROM t;
>
> Regards,
>