[Klug-general] MQSQL to MYSQL

[Mike Evans]

> 
> How about doing the following:
> 
> decide on the tables you care about for copying to mysql
> 
> add update/delete/insert triggers to those tables
> 
> when a record is updated in those tables a log is written by the trigger.
> 
> then you have a daemon on the mysql side to read the log and update the mysql 
> tables.
> 
> the log records are deleted/flagged as the daemon processes them, so if an 
> error occurs you can fix it then begin where it left off.
> 
This is exactly how I've seen it done for IBM's DB2 and it works a 
treat.  I presumed from Dan's original post that MS Enterprise Manager 
had some smarts that made the whole thing simpler.  Silly me - why would 
such a thought have entered my head.  You'd think I'd know better by now :D

You do have to be a little bit careful if you have referential integrity 
on your target tables as there may be no control over the exact order 
that the log statements written are.  (It will mostly be right, but in a 
multi-tasking environment strange things can occasionally happen.)

Mike