Обсуждение: UPDATE sql question

Hi,

What exactly will happen if UPDATE sql statement instructs to update
some columns with the same values as already in the database? Will
Postgres update only different values or it will simply modify all
columns listed in UPDATE sql?

Thanks in advance for any suggestion.


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On Mon, 28 Jul 2003, Andrei Verovski wrote:

> Hi,
>
> What exactly will happen if UPDATE sql statement instructs to update
> some columns with the same values as already in the database? Will
> Postgres update only different values or it will simply modify all
> columns listed in UPDATE sql?

It will update the columns.  Which means lots of dead tuples, which means
vacuuming.