create column postgres code example
Example 1: postgresql add column with constraint
ALTER TABLE customers
ADD COLUMN contact_name VARCHAR NOT NULL;
Example 2: alter table add multiple columns postgresql
ALTER TABLE customer
ADD COLUMN fax VARCHAR,
ADD COLUMN email VARCHAR;
Example 3: postgres how to add field created at
CREATE TABLE my_table
(
id serial NOT NULL,
user_name text,
created_at timestamp with time zone DEFAULT CURRENT_TIMESTAMP //here
)