We may have to modify the table column definition in MySQL database. The syntax is
ALTER table db.tbl CHANGE OLD_COLUMN_NAME NEW_COLUMN_NAME xxx...xxx;
The segment xxx…xxx represents the column definition of the column.
Example.
If I have a column definition
BOOLEAN NOT NULL DEFAULT FALSE COMMENT ‘Abc’
and I like to change the comment text to ‘XYZ’.
I must put full column definition again rather than simply changing the comment parameter. No matter what column parameter you want to change, you have to type all parameter again!
The MySQL statement to do so is
ALTER table db.tbl CHANGE OLD_COLUMN_NAME NEW_COLUMN_NAME BOOLEAN NOT NULL DEFAULT FALSE COMMENT 'XYZ';
