How do I reset sequence numbers to become consecutive?

Question

I\'ve got a mysql table where each row has its own sequence number in a \"sequence\" column. However, when a row gets deleted, it leaves a gap. So...

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Answer 1

Assuming that this is an ID field, you can do this when you insert:

INSERT INTO yourTable (ID)
SELECT MIN(ID)
FROM yourTable
WHERE ID > 1

As others have mentioned I don't recommend doing this. It will hold a table lock while the next ID is evaluated.