SEO

-----BEGIN PGP SIGNED MESSAGE-----
Hash: SHA1


| UPDATE
| orderby SET orderby = orderby +10
| WHERE groupid = 1;
| -> FAILS because of UNIQUE INDEX

One workaround is to do it in two steps, assuming that
orderby is > 0 for all rows you are changing:

BEGIN;
UPDATE mytable SET orderby = -orderby WHERE groupid = 1;
UPDATE mytable SET orderby = -orderby+10 WHERE groupid = 1;
COMMIT;


| UPDATE
| orderby SET orderby = orderby +10
| WHERE groupid IN
| ( SELECT groupid
| FROM TABLE WHERE group_id = 1
| ORDER BY orderby DESC )

No idea what you are trying to do here: try posting the actual SQL
used. However, an ORDER BY has no meaning inside of a subselect
passed to IN, as IN treats the list as bag of values, and does not
care about the internal order.

- --
Greg Sabino Mullane greg@turnstep.com
PGP Key: 0x14964AC8 200606011030
http://biglumber.com/x/web?pk=2529DF...9B906714964AC8

-----BEGIN PGP SIGNATURE-----

iD8DBQFEfvpFvJuQZxSWSsgRAjQlAKDTNIpwbSEk0gcQp2pI7L okG+qwWgCgt/b6
/7ZWYDb4gufE4b0zCHyFZgg=
=4LQ8
-----END PGP SIGNATURE-----



---------------------------(end of broadcast)---------------------------
TIP 1: if posting/reading through Usenet, please send an appropriate
subscribe-nomail command to majordomo@postgresql.org so that your
message can get through to the mailing list cleanly

""Greg Sabino Mullane"" <greg@turnstep.com>
>
> -----BEGIN PGP SIGNED MESSAGE-----
> Hash: SHA1
>
>
> | UPDATE
> | orderby SET orderby = orderby +10
> | WHERE groupid = 1;
> | -> FAILS because of UNIQUE INDEX
>
> One workaround is to do it in two steps, assuming that
> orderby is > 0 for all rows you are changing:
>
> BEGIN;
> UPDATE mytable SET orderby = -orderby WHERE groupid = 1;
> UPDATE mytable SET orderby = -orderby+10 WHERE groupid = 1;
> COMMIT;

Should we invent something to defer the check of uniqueness
to the end of the SQL command?

Regards,
William ZHANG