MySQL Error when dropping index (errno 150)
mysql, mysql-error-1025, sql
Solution
According to this link, the error relates to the definition of the primary key field. The error isn't about the foreign key index.
Check the primary key for the `COMMENTS` table to make sure it does not have the `UNSIGNED` keyword while the `COMMENTS.id_user` foreign key had the UNSIGNED keyword. This keyword was causing the problem - inconsistent type of field.
To fix, add the `UNSIGNED` keyword to the primary key definition for the `COMMENTS` table. Or remove the `UNSIGNED` keyword from the foreign key definition...
Problem
I've got problem with dropping foreign key index, I always get the same error ``` ALTER TABLE `comments` DROP INDEX `id_user` ``` which outputs ``` 1025 - Error on rename of './postuj_cz1/#sql-d834_a0c704' to './postuj_cz1/comments' (errno: 150) ``` The `id_user` on the other table is simple primary key index. I'm using MySQL version 5.0.85