Обсуждение: UPDATE table SET col = (SELECT ...)
Hi,
I found follwing email sent to you in internet.
I am interested in same issue myself.
Did you finally found out any more information about how to Update a column of a table by selecting value from another table?
Hello,
If I understand the SQL references I have read, UPDATEs are allowed to
pull data from SELECT statements, something like
UPDATE table SET col1 = (SELECT val1 FROM table WHERE id = 34),
SET col2 = (SELECT val2 FROM table WHERE id = 34)
WHERE id = 35;
However, the PostgreSQL parser chokes on the 'SELECT'. The
documentation says
UPDATE table SET column = expression [, ...]
[ FROM fromlist ]
[ WHERE condition ]
expression = A valid expression or value to assign to column.
I don't know exactly how to interpret `valid expression'.
--
Eric Marsden
emarsden @ mail.dotcom.fr
It's elephants all the way down
If I understand the SQL references I have read, UPDATEs are allowed to
pull data from SELECT statements, something like
UPDATE table SET col1 = (SELECT val1 FROM table WHERE id = 34),
SET col2 = (SELECT val2 FROM table WHERE id = 34)
WHERE id = 35;
However, the PostgreSQL parser chokes on the 'SELECT'. The
documentation says
UPDATE table SET column = expression [, ...]
[ FROM fromlist ]
[ WHERE condition ]
expression = A valid expression or value to assign to column.
I don't know exactly how to interpret `valid expression'.
--
Eric Marsden
emarsden @ mail.dotcom.fr
It's elephants all the way down
On Wednesday 25 June 2003 11:00, Vangelis-Maria Tougia wrote: > Hi, > I found follwing email sent to you in internet. > I am interested in same issue myself. > Did you finally found out any more information about how to Update a column > of a table by selecting value from another table? Not sure if this has been answered previously, but here goes: > Hello, > > If I understand the SQL references I have read, UPDATEs are allowed to > pull data from SELECT statements, something like > > UPDATE table SET col1 = (SELECT val1 FROM table WHERE id = 34), > SET col2 = (SELECT val2 FROM table WHERE id = 34) ^^^ > WHERE id = 35; The second "SET" is not necessary or allowed and is causing the update to fail. Ian Barwick barwick@gmx.net