Schrödingers MySQL table: exists, yet it does not

Question

I am having the weirdest error of all.

Sometimes, when creating or altering tables, I get the \'table already exists\' error. However, DROP TABLE returns \'#1051 - u

Answer 1

I've seen this issue when the data file is missing in the data directory but the table definition file exists or vise-versa. If you're using innodb_file_per_table, check the data directory to make sure you have both an .frm file and .ibd file for the table in question. If it's MYISAM, there should be a .frm, .MYI and a .MYD file.

The problem can usually be resolved by deleting the orphaned file manually.