The difference between the ALTER column, change column, and MODIFY column of MySQL

Source: Internet
Author: User

ALTER column: Sets or removes the default value for a column (very fast operation) Example:

alter table film alter column rental_duration set default 5; alter table film alter column rental_duration drop default;

Change column: Renaming columns, changing column types, and moving examples of column positions:

ALTER TABLE MyTable CHANGE COLUMN foo bar VARCHAR(32) NOT NULL FIRST; ALTER TABLE MyTable CHANGE COLUMN foo bar VARCHAR(32) NOT NULL AFTER baz; 

MODIFY column: In addition to not naming rename, he does the same job as change COLUMN:

ALTER TABLE MyTable MODIFY COLUMN foo VARCHAR(32) NOT NULL AFTER baz;

The difference between the ALTER column, change column, and MODIFY column of MySQL

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