Re: Is the Halloween problem an issue in Postgres

On 12/2/20 2:02 PM, Thomas Kellerer wrote:
> guyren(at)icloud(dot)com schrieb am 02.12.2020 um 21:27:
>> The Halloween problem is that it is a challenge for the database if
>> you’re updating a field that is also in the WHERE clause of the same
>> query.
>>
>> I just saw a presentation from someone about how in SQL Server he
>> recommended writing changes to a temp table and then writing them to
>> the table as being much more efficient.
>
> It sounds strange to me, that this _is_ actually a problem.
>
> Why exactly is that a problem in SQL Server?

Yeah that was a new one to me. A quick search found:

https://www.sqlshack.com/the-halloween-problem-in-sql-server-and-suggested-solutions/

> And what are the consequences if you do it nevertheless.
>
>
>

--
Adrian Klaver
adrian(dot)klaver(at)aklaver(dot)com