Re: Renumber table rows

[Efraín Déctor <efraindector@xxxxxxxxxxxx>]

Thank you. It really worked.

 

From: David Johnston

Sent: Wednesday, June 06, 2012 3:17 PM

To: 'Efraín Déctor' ; pgsql-general@xxxxxxxxxxxxxx

Subject: RE: Renumber table rows

 

 

Try something along the lines of:

 

UPDATE operador SET idoperador = new_idoperador

FROM (

                SELECT idoperador AS old_idoperador, ROW_NUMBER() OVER (ORDER BY idoperador) AS new_idoperador

                FROM operador

) lookup

WHERE operador.idoperador = lookup.old_idoperador;

 

The basic ideas is to create a lookup table and use it in via a FROM clause attached to the UPDATE.

 

David J.

 

 

From: pgsql-general-owner@xxxxxxxxxxxxxx [mailto:pgsql-general-owner@xxxxxxxxxxxxxx] On Behalf Of Efraín Déctor
Sent: Wednesday, June 06, 2012 2:27 PM
To: pgsql-general@xxxxxxxxxxxxxx
Subject: Renumber table rows

 

Hello.

 

I have a table that his primary key is not ordered is something like this:

 

1      - a

12    - b

123  - c

etc.

 

I want to do an update to make it like this

 

1 – a

2 – b

3 – c

 

I tried this:

 

UPDATE operador SET idoperador=(SELECT row_number() OVER (ORDER BY idoperador) from operador)

 

But it returns this error: more than one row returned by a subquery used as an _expression_ and I know that is because the substring returns more than one row, but how can I use the subquery to perform the update?.

 

Thank you in advance