I wanted to know, will I run into any concurrency problem with this?
This is NOT in a transaction. This code is for Sqlite(prototype), but I plan to use it
Sqlite(prototype)
I may be wrong, but I don't think you would have a problem; the tag_name table I would think would be locked while the UPDATE occurs, so that any other updates waiting to be executed would essentially be queued up rather than occurring concurrently.