|Subject||Re: perf WHERE IN (SUBQUERY)|
> In fact I'm posting that question because this IN statement wasThis approach only works conceptually for snapshot transactions. For
> originaly done in Oracle without any performance problem, Oracle First
> read (once) the subquery on B and reads A using A_ID index ...
read committed transactions, how would you know that an additional
record was not added to B whilst fetching the records from A?