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Test of Outer Join

SELECT S.Name AS Street, U.* FROM Streets S LEFT OUTER JOIN Users U ON U.Streetid = S.Id;

DROP TABLE IF EXISTS OuterJoinStreetUser; CREATE TABLE OuterJoinStreetUser AS SELECT S.Name AS Street, U.* FROM Streets S LEFT OUTER JOIN Users U ON U.Streetid = S.Id; SELECT Street, Count(Username) AS COUNT FROM OuterJoinStreetUser GROUP BY Street;

DROP TABLE IF EXISTS Streets; CREATE TABLE Streets ( ID INT PRIMARY KEY, Name VARCHAR(100) ); DROP TABLE IF EXISTS users; CREATE TABLE users ( Username VARCHAR(100) PRIMARY KEY, StreetID INT REFERENCES Streets ( ID ) ); INSERT INTO Streets VALUES ( 1, '1st street' ), ( 2, '2nd street' ), ( 3, '3rd street' ), ( 4, '4th street' ), ( 5, '5th street' ); INSERT INTO users VALUES ( 'Pol', 1 ), ( 'Doortje', 1 ), ( 'Marc', 2 ), ( 'Bieke', 2 ), ( 'Paulien', 2 ), ( 'Fernand', 2 ), ( 'Pascal', 2 ), ( 'Boma', 3 ), ( 'Goedele', 3 ), ( 'Xavier', 4 );

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