Re: UPDATE with JOIN

On Tue, 24 May 2005 16:31:15 -0400, Keith Worthington wrote
> On Tue, 24 May 2005 14:26:21 -0400, Tom Lane wrote
> > "Keith Worthington" <keithw(at)narrowpathinc(dot)com> writes:
> > > UPDATE tbl_line_item
> > > SET tbl_line_item.reviewed = TRUE
> > > FROM tbl_item
> > > ON ( tbl_line_item.item_id = tbl_item.id )
> > > WHERE item_type = 'DIR';
> >
> > Of course that's not valid JOIN syntax (no JOIN keyword, and no
> > place to put it either). You have to use the WHERE clause:
> >
> > UPDATE tbl_line_item
> > SET tbl_line_item.reviewed = TRUE
> > FROM tbl_item
> > WHERE tbl_line_item.item_id = tbl_item.id
> > AND item_type = 'DIR';
> >
> > regards, tom lane
> >
>
> Thanks Tom
>
> I couldn't figure out how to do the JOIN part of that statement.
> Using your instruction all I had left to do was drop the
> qualification off the SET column and it worked. :-) Thanks again.
>
> UPDATE tbl_line_item
> SET reviewed = TRUE
> FROM tbl_item
> WHERE tbl_line_item.item_id = tbl_item.id
> AND item_type = 'DIR';
>
> Kind Regards,
> Keith
>
> ---------------------------(end of broadcast)---------------------------
> TIP 7: don't forget to increase your free space map settings

Replying to myself in the hopes of helping someone else.

I wondered (and needed to know) if this concept could be extended to use
multiple tables? The answer is yes. The syntax of the query seemed different
to me so I repeat it here.

UPDATE tbl_line_item
SET reviewed = TRUE
FROM tbl_item_bom,
tbl_item
WHERE tbl_line_item.so_number = tbl_item_bom.so_number
AND tbl_line_item.so_line = tbl_item_bom.so_line
AND tbl_line_item.item_id::text = tbl_item.id::text
AND tbl_item_bom.so_subline IS NOT NULL
AND ( tbl_item.item_type::text = 'THIS'::text
OR tbl_item.item_type::text = 'THAT'::text
OR tbl_item.item_type::text = 'OTHR'::text
);

Kind Regards,
Keith