We can use the "COMMENT" keyword with the ALTER TABLE command to add comments on the column while modifying the column. For example, if we want to add a comment in the "id" column of the table "testing", the following query will do this -
mysql> ALTER TABLE testing MODIFY id INT COMMENT 'id of employees'; Query OK, 0 rows affected (0.07 sec) Records: 0 Duplicates: 0 Warnings: 0
With the following query, we can check it in the comment field of the column.
mysql> Show full columns from testing\G *************************** 1. row *************************** Field: id Type: int(11) Collation: NULL Null: NO Key: PRI Default: 0 Extra: Privileges: select,insert,update,references Comment: id of employees *************************** 2. row *************************** Field: Name Type: varchar(20) Collation: latin1_swedish_ci Null: YES Key: Default: NULL Extra: Privileges: select,insert,update,references Comment: 2 rows in set (0.05 sec)
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