Run database updates on live Magento store?

I have been asking a few questions recently to work out how to change our Magento store's product codes.

The answer was to run this command within phpmyadmin:

UPDATE `catalog_product_entity` SET `sku` =  RIGHT(CONCAT('00000000', sku), 8)

It worked perfectly, changing all of our product codes from:

63
3433
432
42342343

to:

00000063
00003433
00000432
42342343

The problem is; everytime I run that command it correctly changes the product codes - but all products are then 404'ing. I t开发者_如何学Pythonhen refreshed the indices and found that the were locked. I got the following error:

Cannot initialize the indexer process.

so I ran the following commands via SSH:

rm -rf downloader/pearlib/cache/*
rm -rf downloader/pearlib/download/*
rm -rf var/cache/*
rm -rf var/session/*
rm -rf var/report/*
rm -rf var/tmp/*
rm -rf var/locks/*

but the index processes still wouldn't run. I have now completely messed up the database and am waiting for a support tech to try and fix the problem. I will likely be recovering the database from the backup I took before I ran the SQL command.

I am trying to work out how to run this SQL command without messing the Magento (1.5) locks etc. up so that the products don't 404.

Ok, so the answer was simple.

1. Disable all cache options
2. Re-index the indices.
3. Run the SQL command.
4. Re-index the indices.
5. Refresh then re-enable the cache

Hope this helps someone else in future!