Introduction
Defining columns with DEFAULT
Adding DEFAULT to existing tables
Instruction
Very well done! Now, let's take a look at how we can add a DEFAULT constraint to an existing table. The table looks like this:
CREATE TABLE therapist ( id integer PRIMARY KEY, full_name varchar(32) DEFAULT 'anonymous', price decimal(5, 2), location varchar(32) DEFAULT 'unknown' );
We want to add a default value for the price column. To do so, we can write:
ALTER TABLE therapist ALTER COLUMN price SET DEFAULT 60.00;
The code above will add a default value of 60.00 to the price column in the therapist table.
Exercise
A furniture store has the following table to keep track of the desks they offer:
CREATE TABLE desk ( id integer PRIMARY KEY, model_name varchar(32), price decimal(6, 2) DEFAULT 304.91, is_customizable boolean );
Your task is to add a default value of FALSE to the is_customizable column.
