Re: how to write correctly this update ?

[Pierre Couderc]

On 5/22/19 3:19 PM, Rob Sargent wrote:

Don’t use the alias on the column(s) being set.
This passed the parser:
UPDATE  personnes T1 SET nom_naiss=T1.nom FROM  personnes T2, personnes T3
WHERE T1.id=T2.id_mere AND T2.id_pere=T3.id AND T1.nom != T3.nom;

Wow, fine ! you got  it!

(I have no data in my table so I can’t confirm the logic.  You seem to want to 
update mother’s maiden name if her current (sur)name doesn’t match that of the 
father of (one of?) her children?  That might be a serious leap of faith.)

Now I check manually... ;)

On May 22, 2019, at 6:43 AM, Pierre Couderc <pie...@couderc.eu> wrote:

I have tried many ways to update a table  :

UPDATE  personnes T1 SET T1.nom_naiss=T1.nom FROM  personnes T2, personnes T3
WHERE  ....;


UPDATE  personnes T1 SET T1.nom_naiss=T1.nom FROM  personnes T1, personnes T2, 
personnes T3
WHERE ..;


In my case , where clause is : WHERE T1.id=T2.id_mere AND T2.id_pere=T3.id AND 
T1.nom != T3.nom;

Thanks.

PC