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My site's been chugging along on mysql 4.0.27 for years. Finally realized that, yeah, maybe it was time to upgrade. Except the upgrade path from 4.0 to 5.X is to first upgrade to the 4.1 RPMs.

Except, of course, MySQL has taken those down as they're past supporting them.

Does it make any sense, are there any potholes, if I just take my site down to maintenance mode, remove the 4.0.X off my server and then install 5.X fresh, pointing it to the data files? Or doing a mysqldump first, then importing into the 5.X?


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what is your OS ? – Prix Aug 22 '10 at 4:19
up vote 1 down vote accepted

You will most likely need to do a MySQL dump of the data first as the data files are unlikely to be compatible. I know this is the case for 5.0.77 to 5.1., but I can't comment for sure for 4.0. to 5.*.

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You don't need to do this for 5.0 -> 5.1, all you do is run mysql_upgrade after the 5.1 is running to fix your bits. I would, though, recommend a dump/import for 4.0 to 5.1 - it's safe and easy. – troyengel Aug 22 '10 at 15:00
+1 Agreed. The safest is to dump all your data, upgrade to a fresh MySQL 5 server and reimport your data. This will ensure your upgrade goes smoothly. Take special care when dumping the mysql database though, as the structures have changed in MySQL version. It might be easier to recreate your user permissions on the new server instead of importing the mysql DB. – vmfarms Aug 22 '10 at 15:30

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