DROP COLUMN - (PostgreSQL Table)

In PostgreSQL, the DROP COLUMN command is used to remove a column from a table. In this tutorial, we'll discuss the syntax, example, output, explanation, use, important points, and summary of the DROP COLUMN command in PostgreSQL.

Syntax

The basic syntax for dropping a column in PostgreSQL is as follows:

ALTER TABLE table_name
DROP COLUMN column_name;

• table_name: The name of the table that the column belongs to.
• column_name: The name of the column to be dropped.

Example

Let's take a look at an example of using DROP COLUMN in PostgreSQL:

ALTER TABLE employees
DROP COLUMN hire_date;

In this example, we are dropping the hire_date column from the employees table.

Explanation

In PostgreSQL, the ALTER TABLE statement is used to modify an existing table. The DROP COLUMN command is used to remove a column from a table.

When using the DROP COLUMN command, you must provide the name of the table and the name of the column that you want to drop.

Use

The DROP COLUMN command is used to remove a column from a table. This is useful when you no longer need a particular column or when you want to clean up your table structure.

Important Points

• When you drop a column from a table, any data stored in that column will also be removed.
• You cannot drop a column that is part of a primary key constraint or a foreign key constraint.
• If you drop a column that is used by a view, you will also need to update the view accordingly.

Summary

In this tutorial, we discussed the DROP COLUMN command in PostgreSQL. We covered the syntax, example, output, explanation, use, and important points of the DROP COLUMN command. With this knowledge, you can now use the DROP COLUMN command to remove a column from a table in PostgreSQL.