Open In App
Related Articles

PostgreSQL – ADD COLUMN

Improve
Improve
Improve
Like Article
Like
Save Article
Save
Report issue
Report
PostgreSQL has an ADD COLUMN statement to add one or more columns to an existing database table. To add a new column to an existing table, you use the ALTER TABLE ADD COLUMN statement.
Syntax:
ALTER TABLE table_name
ADD COLUMN new_column_name data_type;
Let’s analyze the above syntax:
  • First, specify the table that you want to add a new column in the ALTER TABLE clause.
  • Second, indicate the column name with its attribute such as data type, default value, etc., in the ADD COLUMN clause.
While adding a new column to the table, PostgreSQL appends it at the end of the table. PostgreSQL has no option to set the position of the new column in the table. Example 1: First, we create a table (say, village), with village_id and village_name columns using the below statement:
CREATE TABLE village(
    village_id SERIAL PRIMARY KEY,
    village_name VARCHAR NOT NULL
);
Now we add a district column to the table as below:
ALTER TABLE village
ADD COLUMN district VARCHAR;
Now we can verify if the column has been added using the below statement:
SELECT * FROM village;
Output: Example 2: First, we create a table (say, cars), with car_id and car_name columns using the below statement:
CREATE TABLE cars(
    car_id SERIAL PRIMARY KEY,
    car_name VARCHAR NOT NULL
);
Now we add a modelcolumn to the table as below:
ALTER TABLE cars
ADD COLUMN model VARCHAR;
Now we can verify if the column has been added using the below statement:
SELECT * FROM cars;
Output:

Last Updated : 28 Aug, 2020
Like Article
Save Article
Previous
Next
Share your thoughts in the comments
Similar Reads