SQL Reference - BOOLEAN

Example

CREATE TABLE employees (
    id SERIAL PRIMARY KEY,
    name VARCHAR (100),
    is_manager BOOLEAN
);

INSERT INTO employees (name, is_manager)
VALUES ('John Doe', TRUE),
       ('Jane Doe', FALSE);

SELECT * FROM employees WHERE is_manager = TRUE;

Output

 id |   name   | is_manager
----+----------+------------
  1 | John Doe | t

Explanation

In the example provided, a table employees is created with a column is_manager of BOOLEAN type. Two rows are then inserted into the table, with ‘John Doe’ having a is_manager value of TRUE and ‘Jane Doe’ having an is_manager value of FALSE. The SELECT statement retrieves all employees for which the is_manager field is TRUE, thus the output includes the record for ‘John Doe’ only.

Example

CREATE TABLE Employee (
  emp_id int,
  is_manager BOOLEAN
);

INSERT INTO Employee (emp_id, is_manager)
VALUES (1, TRUE),
       (2, FALSE);

SELECT * FROM Employee;

Output

| emp_id | is_manager |
|--------|------------|
| 1      | 1          |
| 2      | 0          |

Explanation

In this case, SQLite does not have built-in BOOLEAN type. However, it uses INTEGER to store Boolean values. SQLite uses 0 for FALSE and 1 for TRUE. The table Employee created includes a column is_manager of type BOOLEAN. By inserting the values into Employee, when fetching the data from the table, it shows 1 for TRUE input and 0 for FALSE input.