Thanks Josh. So far I've identified the following tables that seem to re-use the
U_Number...

Table---------------Columns
w3t_Last--------------L_Uid
w3t_Messages-----M_Uid, M_sender
w3t_Moderators----M_Uid
w3t_Posts------------B_PosterId, B_LastPosterId

I'm unsure about these...

Table---------------Columns
w3t_Online----------O_Uid
w3t_Ratings---------R_What
w3t_Subscribe------S_Uid

It shouldn't be hard to catch all the necessary tables with a simple script. However I want to be sure I've identified all the fields I need to change. Can you take a look at this and see if I've missed anything? Many thanks.

I'll try it out on one user and if I break the database, I can always reverse the changes.

Photopost OTOH, is another matter...

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So if you change a user number in the user table, be sure to search and make the same adjustment in EVERY table that has user numbers. (Which is most of them).
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