How to change Column size of varchar type in mySQL?

Use the following command:

ALTER TABLE table_name MODIFY COLUMN column_name VARCHAR(100);

Or use CHANGE, but that means you have to give the column name twice (because CHANGE allows you to change the name of the column too).

ALTER TABLE table_name CHANGE COLUMN column_name column_name VARCHAR(100);

🚨 Don't put the column name in single-quotes. Single-quotes are for string literals or date literals.

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