Обсуждение: What is the syntax for UPDATE from one table to another?

Hello,

What is the proper syntax for updating a column inone table from
a column in another?

I have tried this:

UPDATE destination_table FROM source_table SET
destination_table.column_one = source_table.column_b WHERE constraint;

This fails, so I must have the syntax incorrect.

Thanks for any help,

Pete

On Mar 12, 2004, at 12:40 PM, pw wrote:

>
> Hello,
>
> What is the proper syntax for updating a column inone table from
> a column in another?
>
> I have tried this:
>
> UPDATE destination_table FROM source_table SET
> destination_table.column_one = source_table.column_b WHERE constraint;
>

update destination_table set column_a = (select column_b from
source_table where blah blah blah ) where blah blah blah

You can reference the values in destination_table inside the select.
--
Jeff Trout <jeff@jefftrout.com>
http://www.jefftrout.com/
http://www.stuarthamm.net/

On Fri, Mar 12, 2004 at 09:40:13 -0800,
  pw <p.willis@telus.net> wrote:
>
> Hello,
>
> What is the proper syntax for updating a column inone table from
> a column in another?
>
> I have tried this:
>
> UPDATE destination_table FROM source_table SET
> destination_table.column_one = source_table.column_b WHERE constraint;
>
> This fails, so I must have the syntax incorrect.

If you check the documentation you will see that SET is supposed to be before
FROM.

Thanks to everyone who helped.
I found the solution just by tooling with the SQL syntax.

FYI,  the correct syntax is:


UPDATE destination_table SET dest_column=A FROM
(SELECT src_column as A, src_link_col FROM src_table) AS  J
WHERE src_link_col=dst_link_col;


Pete


pw wrote:

>
> Hello,
>
> What is the proper syntax for updating a column inone table from
> a column in another?
>
> I have tried this:
>
> UPDATE destination_table FROM source_table SET
> destination_table.column_one = source_table.column_b WHERE constraint;
>
> This fails, so I must have the syntax incorrect.
>
> Thanks for any help,
>
> Pete
>
>
>
>
>
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