To add multiple columns to an existing table in PostgreSQL, you can use the ALTER TABLE statement with the ADD COLUMN clause. Here’s the syntax for adding multiple columns at once: Syntax ALTER TABLE table_name ADD COLUMN column1_name data_type1, ADD COLUMN...
Drop column from existing table How to drop column from existing table. Alter syntax and example. Syntax ALTER TABLE table_name DROP COLUMN column_name RESTRICT; Create table CREATE TABLE users( userid numeric not null default nextval('seq_users'::regclass), username varchar(100), userpass varchar(250), usermail varchar(50),...
To drop multiple columns from a PostgreSQL table using the ALTER TABLE statement, you can follow these steps: Connect to your PostgreSQL database using a client or command-line interface. Syntax Execute the following ALTER TABLE statement: ALTER TABLE table_name DROP COLUMN...
Rename column from existing table How to rename column from existing table. Alter syntax and example. Syntax ALTER TABLE table_name RENAME COLUMN old_col_name TO new_col_name; Create table CREATE TABLE users( userid numeric not null, username varchar(100), userpass varchar(250), usermail varchar(50), address...
Rename name of existing table How to rename the name of existing table. Alter syntax and example. Syntax ALTER TABLE old_table_name RENAME TO new_table_name; Example Rename column ALTER TABLE customers RENAME TO buyers;...