I have 2 databases with MyISAM tables running on a Windows 2008 Server. These databases are about 20GB in size with a few tables with millions of rows. My question regards backing them up on a weekly basis. Currently I do some updates once a week, and then I go to the data folder and copy the physical folders representing the databases to another drive on the server, and then rar everything up.

This process takes about 45 minutes and during that time certain functionality of my website cannot be used as during the copying, the tables get blocked. I have seen that you can LOCK and FLUSH tables so that they can still be used while they are being copied. So does LOCKing the tables allow concurrent SELECTs?

I do not know exactly how to go about this and I would greatly appreciate if anyone could help me with how I could synchronize the lock/flush statements with the copying of the physical data and then the subsequent unlocking, and how I could possibly automate (possibly script to a dos batch file) this process?

Thanks in advance, Tim