SQL Exercise: List the nurses who are yet to be registered

Last update on December 20 2024 12:00:56 (UTC/GMT +8 hours)

1. From the following table, write a SQL query to find out which nurses have not yet been registered. Return all the fields of nurse table.

 employeeid |      name       |  position  | registered |    ssn
------------+-----------------+------------+------------+-----------
        101 | Carla Espinosa  | Head Nurse | t          | 111111110
        102 | Laverne Roberts | Nurse      | t          | 222222220
        103 | Paul Flowers    | Nurse      | f          | 333333330

Sample Solution:

SELECT *
FROM nurse
WHERE registered='false';

Sample Output:

  employeeid |     name     | position | registered |    ssn
 ------------+--------------+----------+------------+-----------
         103 | Paul Flowers | Nurse    | f          | 333333330
 (1 row)

Explanation:

The given query in SQL that retrieves all rows from the nurse table where the value of the registered column is 'false'.

The WHERE clause filters the results and returns only the rows where the value of the registered column is 'false'.

Pictorial presentation:

Alternative Solution:

Using NOT Operator:

SELECT *
FROM nurse
WHERE NOT registered;

Explanation:

This query uses a NOT operator that negates the value of registered, effectively finding the nurses who are not registered.

Relational Algebra Expression:

Relational Algebra Tree:

Practice Online

E R Diagram of Hospital Database:

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