postgresql add table code example

Example 1: create table in postgresql

-- Example table
 CREATE TABLE accounts (
	user_id serial PRIMARY KEY,
	username VARCHAR ( 50 ) UNIQUE NOT NULL,
	password VARCHAR ( 50 ) NOT NULL,
	email VARCHAR ( 255 ) UNIQUE NOT NULL,
	created_on TIMESTAMP NOT NULL,
        last_login TIMESTAMP 
);

Example 2: postgres create table

-- Basic table creation
CREATE TABLE table_name(
   column1 datatype,
   column2 datatype,
   column3 datatype,
   .....
   columnN datatype,
   PRIMARY KEY( one or more columns )
);

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
)

Example 4: alter table add column postgres

Alter Postgres Table