Problem with migration number

I have recently had to reload my computer. I don’t know if this if
relevant at all to this problem, but wanted to mention it.

I have an application that I’m needing to make some changes to. To
prepare for it, I’m doing a new migration. In the db/migrate directory,
the last migration was 019_… My new migration is 020_…

The problem that I’m having is that rake seems to want to rerun
migrations beginning with 001. This causes it to error off. I’ve looked
at schema_info and schema_migrations in the database. Both have their
version set to 19.

What would be causing this? It would be a snap to go into mysql and just
do the migration manually, but I’d rather stay in the rails framework.

Thanks in advance