Hello.

> Does this have anything to do with the variable:
>
> | tx_isolation                    | REPEATABLE-READ                    |

It seems it is. If you use InnoDB only due to speed issues, change
the transaction isolating level to READ UNCOMMITED. See:
 http://dev.mysql.com/doc/refman/5.0/en/innodb-transaction-isolation.html

This might be helpful as well:
  http://dev.mysql.com/doc/refman/5.0/en/innodb-tuning.html
  http://dev.mysql.com/doc/refman/5.0/en/table-locking.html



George Law wrote:
> Hi All,
> 
> I just had a question on selects on a innodb table.
> 
> Looking on google, I find that there are different types of selects:
> select .... IN SHARE MODE and FOR UPDATE
> 
> I am administering a database with a fairly large innodb table.  I am
> running into
> problems with one of my users insisting on using selects on a datestamp
> field that is not indexed.  Moreover, she is doing selects/updates like :
> 
> select .... from .... where left(start_time,10)= '2006-01-10'
> update xxx set ... where .... left(start_time,10)= '2006-01-10'
> 
> I also cannot get through to her to use BEGIN/COMMIT on her updates.
> 
> While her perl scripts are running, I am finding that I have imports
> running in the background to "load data infile" into the same table she
> is reading from/updating.  These updates happen 6 times an hour. 
> Probably 1 in 6 import fails, presumably because one of her queries has
> the table locked.
> 
> Other times I have seen this happen when she is doing a bulk select and
> importing into another table.
> 
> What is the default mode for SELECT statements with INNODB table.  I had
> assumed that it would always allow for inserts to happen elsewhere in
> the table (ie - SHARED mode).  That was my big reason for using INNODB
> for this table.  It just doesn't seem right that the whole table seems
> to get locked on the select.
> 
> Does this have anything to do with the variable:
> 
> | tx_isolation                    | REPEATABLE-READ                    |
> 
> 
> Thanks!
> 
> George Law
> 
> 
> 
> 


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