Re: Table marked as crashed and last (automatic?) repair failed

[Rick James]

The entire tree: Everything under /.../mysql/..., including
mysql/mysql/ -- where the GRANTs are stored (user, db, host, ...)
mysql/yourdb/ -- directories corresponding to your database(s)
mysql/ibdata1 (or wherever it is) -- critical stuff for InnoDB
mysql/iblog* -- ditto
etc

If you copy my.cnf (my.ini), be sure to change server_id -- that value MUST be different between machines.

The leaf nodes of the BTree (InnoDB):
* For the 'data' -- contains entire rows
* For a secondary 'index' -- contains the PRIMARY KEY: It then uses this to find the actual record by drilling down the Data BTree.
Those two structures are virtually identical; it's just a question of what you find when you get to the leaf.

MyISAM uses a BTree for each index, including the PK, but not for the data. Its leaf nodes have pointers into the data file (.MYD). All the indexes are in the .MYI file. The MYD is just data; virtually no structure. (There is a little bit of structure to handle deleted rows.)