"You can rename a column using a CHANGE old_col_name create_definition clause. To do so, specify the old and new column names and the type that the column currently has. For example, to rename an INTEGER column from a to b, you can do this:
mysql> ALTER TABLE t1 CHANGE a b INTEGER;
If you want to change a column's type but not the name, CHANGE syntax still requires two column names even if they are the same. For example:
mysql> ALTER TABLE t1 CHANGE b b BIGINT NOT NULL;
However, as of MySQL Version 3.22.16a, you can also use MODIFY to change a column's type without renaming it:
mysql> ALTER TABLE t1 MODIFY b BIGINT NOT NULL;"