The ALTER TABLE Statement
To remove a column from a table, we have to use the ALTER TABLE statement.
The ALTER TABLE statement is used to add, delete, or modify columns in an existing table.
The ALTER TABLE statement is also used to add and drop various constraints on an existing table.
DROP COLUMN
We want to remove the column named color from the cars table.
To remove a column, use the DROP COLUMN statement:
Example
Remove the color column:
ALTER TABLE cars
DROP COLUMN color;
Result
ALTER TABLE
Display Table
To check the result we can display the table with this SQL statement:
Example
SELECT * FROM cars;
As you can see in the result, the color column has been removed from the cars table.
PostgreSQL Exercises
Test Yourself With Exercises
Exercise:
Write the correct SQL statement to remove a column from a table.
Remove the column year from the table cars: cars year;
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