PostgreSQL

PostgreSQL DROP COLUMN

Remove an unwanted column from an existing PostgreSQL table with ALTER TABLE.

The ALTER TABLE statement

To remove a column from a table, use the ALTER TABLE statement. It can also be used to add or modify columns and to add or drop constraints on an existing table.

DROP COLUMN

We will remove the column named color from the products table. Use DROP COLUMN to remove the column and the data stored in it:

Remove the color column with this statement: 

ALTER TABLE products
DROP COLUMN color;

Result

PostgreSQL reports:

ALTER TABLE

This confirms that the table structure was changed successfully.

Display the table

To check the result, display the table with this statement:

SELECT * FROM products;

The color column is no longer included in the result. Dropping a column also removes all data stored in that column, so confirm the column is no longer needed before executing the statement.

Warning: Check dependencies and update application code before dropping a column. Use DROP COLUMN IF EXISTS color when you want to avoid an error if the column has already been removed.

Further Reading

Continue learning with these related tutorials:

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