[Pgpool-general] Replication Flawed?

[Tatsuo Ishii]

> >There could be many ways. One of them is table locking as I suggested.
> 
> After consideration you are indeed correct that locking a table before executing a query can produce consistent data.  However I am not too favourable to shifting some of the responsibility of a HA solution upon the application itself.  For me, whatever solution is offered should be transparent to the application otherwise you are only going to run into further problems by splitting this responsibility.
> 
> The idea of LOCK TABLES has other drawbacks:
> 
> *) Not an SQL standard, therefore some interpretation is required by the application of the  database underneath e.g. 'LOCK TABLE t WRITE' (MySQL) or 'LOCK TABLE films IN EXCLUSIVE MODE' (Postgres)
> 
> *) Isn't table level locking going to deny you the extra concurrency of row-level locking?  Although perhaps you could argue the ordering of statements e.g. Sequoia would have the same effect on performance
> 
> Thanks,

Of course the table locking kills the row-level locking. The Sequoia's
way will be even worse than the table locking, I guess. I will be glad
to hear better solution than those.
--
Tatsuo Ishii
SRA OSS, Inc. Japan