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Can I Add or Modify Comments on MySQL Columns?

Barbara Streisand

Oct 30, 2024 pm 12:57 PM

Can I Add or Modify Comments on MySQL Columns?

Adding Comments to MySQL Columns

Question:

Can you add or modify comments on MySQL columns? The official documentation does not explicitly mention this feature.

Answer:

Yes, you can add or modify comments on MySQL columns using the ALTER TABLE statement.

For Column Comments:

To add or modify a comment on a specific column, use the following syntax:

ALTER TABLE <table_name> CHANGE <column_name> <column_name> <data_type> COMMENT '<comment>'</comment></data_type></column_name></column_name></table_name>

For example, to add a comment to the id column in the user table:

ALTER TABLE `user` CHANGE `id` `id` INT( 11 ) COMMENT 'id of user'

This will add the comment 'id of user' to the id column.

Note: The CHANGE clause is used to modify the column definition while preserving its existing data.

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