on noop operation, drop ghost table at end

[shlomi-noach]

To iterate on this; maybe on noop we might want to keep the ghost table around? e.g. to see how it looks after migration?

[SuperQ]

I would prefer to keep all tables after operations in order to examine the results.

[shlomi-noach]

What I don't intend to do is go the pt-online-schema-change way, of infinitely prepending _ if a table name already exists.

It's common practice to issue a noop migration first, followed by a --execute one. I'm looking for the correct way of making this nice and friendly to everyone.

[SuperQ]

In LHM, we save the original table with a datestamp to avoid this.

[shlomi-noach]

The next concern with that, which is, granted, most of the time not such a big deal, is the max number of characters in table name. It is 64 chars, and I cannot presume to be able to append as large suffix as I would like to.
Having said that, if table name is known to be short enough, that can be arranged.

[SuperQ]

Yea, name length is an issue. But the 99% case we can handle things.

One option for NOOP mode is to simply grab the output of SHOW CREATE TABLE or other things before dropping.