37 lines
869 B
SQL
37 lines
869 B
SQL
USE tutorial;
|
|
|
|
/* Cartesian product (every row combined with every other row) and filter out rows */
|
|
SELECT
|
|
em.id AS 'Employee ID',
|
|
em.surname AS 'Surname',
|
|
em.forename AS 'forename',
|
|
at.id AS 'Title ID',
|
|
at.name AS 'Title'
|
|
FROM
|
|
Employee AS em,
|
|
AcademicTitle AS at
|
|
WHERE
|
|
em.surname LIKE 'Ma%'
|
|
AND at.id = em.academicTitleId;
|
|
|
|
/* only select rows which have a matching (true) condition */
|
|
SELECT *
|
|
FROM Employee AS em
|
|
INNER JOIN AcademicTitle AS at
|
|
ON em.academicTitleId = at.id
|
|
WHERE
|
|
em.surname LIKE 'Ma%';
|
|
|
|
SELECT
|
|
em.surname,
|
|
em.roomId AS 'Employee Room',
|
|
room.id AS 'Room ID',
|
|
room.name AS 'Room name'
|
|
FROM Employee as em
|
|
INNER JOIN Room as room ON em.roomId = room.id
|
|
WHERE room.name LIKE 'a%';
|
|
|
|
SELECT
|
|
count(*) AS Anzahl
|
|
FROM Employee em
|
|
LEFT JOIN PostalLocation post ON post.id = em.postalLocationId; |