Re: How to speed up Exclusive Locking

On Tue, 5 Dec 2006 10:18:21 +0000, David Goodenough  wrote:

[...]

> The first bits of the sync are done without locking the source tables, and
> I do these until I find less than some suitable threshold of records
> needing
> to be updated.  Then I lock the source tables and do the final sync.
> 
> The statements issued to lock each table is:-
>  LOCK TABLE table IN EXCLUSIVE MODE; SELECT 1 FROM table;
> 

So why selecting '1' for each row after locking the relation before? I don't 
know HA-JDBC but this looks really useless. Remove the SELECT and use 
the LOCK TABLE command within the transaction which does the sync for you.

Bernd