[Q]updating multiple rows with Different values

Hello,
searched documentation, FAQ and mailing list archives
(mailing list archive search is volumous :-) )

but could not find an answer:

I would like to be able to update
several rows to different values at the same time

In oracle this used to be called Array update or 
'collect' update or 'bulk' update -- but those
keywords did not bring anything for Postgresql.

for example tbl_1 has two columns id and col1


update tbl_1  set
   col1=3  where id=25,
   col1=5  where id=26


I am using PHP PDO (and hoping that if there is a mechanism
within postgresql to do that PDO will support it as well).


Thank you in advance,
VSP

-- 
  V S P
  toreason@fastmail.fm

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