Migrating a single site to Multisite

Dear All

I have a new multisite install of Drupal which works perfectly with new websites. My aim is to move about 10 sites which are currently configured for a single install over to this new system, I am, however, having a problem with converting the single install’s database to work with a multisite system. I’m running the following SQL within the MySQL command line tool but I receive an error telling me that. Table ‘sites__db.FILES’ doesn’t exist.

USE sites__db;
UPDATE files SET filepath=REPLACE (filepath, 'default', 'mydomain.co.uk');

Clearly, I am doing something wrong. Can anybody help?

Many thanks

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