SQLCourse

SQL exercises from sqlcourse.com.

Snippets

Code used for these exercises.

Comparison Operators

=     -- Equal
>     -- Greater than
<     -- Less than
>=    -- Greater than or equal
<=    -- Less than or equal
<>    -- Not equal to
LIKE  -- Compare a value to similar values using wild card operators

When using LIKE, the percent sign % can be used as a wild card to match any character that might appear before or after the characters specified.

Examples:

Display the first and last names for everyone whose last name ends in an "ay".

SELECT first, last
  FROM empinfo
 WHERE last LIKE '%ay';

Select first name, last name, and salary for anyone with "Programmer" in their title.

SELECT firstname, lastname, salary
  FROM employees_jnd2017
 WHERE title LIKE '%Programmer%';

Selecting Data

SELECT first, last, city
  FROM empinfo
 WHERE city <> 'Payson';

Creating Tables

CREATE TABLE employees_jnd2017
            (firstname VARCHAR(15),
             lastname  VARCHAR(20),
             title     VARCHAR(30),
             age       NUMBER(2),
             salary    NUMBER(6));

Inserting Into a Table

INSERT INTO employees_jnd2017
            (firstname, lastname, title, age, salary)
     values ('Jonie', 'Weber', 'Secretary', 28, 19500);

Updating Records

UPDATE employees_jnd2017
   SET lastname = 'Weber-Williams'
 WHERE firstname = 'Jonie' AND lastname = 'Weber';

Deleting Records

DELETE FROM employees_jnd2017
      WHERE firstname = 'Jonie'
        AND lastname = 'Weber-Williams';

Dropping a Table

DROP TABLE employees_jnd2017;