On 6/12/24 15:48, Ron Johnson wrote:
> On Wed, Jun 12, 2024 at 5:28 PM Rich Shepard
> <rshepard(at)appl-ecosys(dot)com> wrote:
>
> I have a table with 3492 rows. I want to update a boolean column from
> 'false' to 'true' for 295 rows based on the value of another column.
>
> Is there a way to access a file with those condition values? If
> not, should
> I create a temporary table with one column containing those
> values, or do I
> write a psql script with 295 lines, one for each row to be updated?
>
>
> A plain UPDATE might work.
> UPDATE to_be_updated a
> SET bool_col = true
> FROM other_table b
> WHERE a.pk <http://a.pk> = b.pk <http://b.pk>
> AND b.field3 = mumble;
>
> (You can join them, right?)
Add "begin;" to that and try it. If you don't get exactly UPDATE 295
reported, then "rollback;";