Re: Renumber table rows

Thank you. It really worked.

From: David Johnston
Sent: Wednesday, June 06, 2012 3:17 PM
To: 'Efraín Déctor' ; pgsql-general(at)postgresql(dot)org
Subject: RE: [GENERAL] 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(at)postgresql(dot)org [mailto:pgsql-general-owner(at)postgresql(dot)org] On Behalf Of Efraín Déctor
Sent: Wednesday, June 06, 2012 2:27 PM
To: pgsql-general(at)postgresql(dot)org
Subject: [GENERAL] 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