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Open Source Technologies

Notes mysql>ALTER TABLE student add marks int(3);
Then the table structure becomes:

Using ALTER statement you can change the data type of a column and the name of an existing
table.

Syntax for changing the data types of a column.
ALTER TABLE table_name MODIFY column_name type.

or

ALTER TABLE table_name CHANGE column_name new column_name type.

The difference between MODIFY and CHANGE is that, in case of CHANGE
you can change name of column which is not possible by using MODIFY that’s
why change takes two names?

Syntax for changing the table name:
ALTER TABLE table_name RENAME AS new_table_name

Using ALTER statement you can remove a column from a table:
Syntax is:

ALTER TABLE table_name DROP COLUMN col_name;

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