SQLZOO, CREATE TABLE with a composite primary key

CREATE TABLE with a composite primary key

Oracle
A composite key has more than one attribute (field). In this example we store details of tracks on albums - we need to use three columns to get a unique key - each album may have more than one disk - each disk will have tracks numbered 1, 2, 3... The primary key must be different for each row of the table. The primary key may not contain a null.	Run the tidy code silently CREATE TABLE track( album CHAR(10), disk INTEGER, posn INTEGER, song VARCHAR(255), PRIMARY KEY (album, disk, posn) )
Specific to Oracle
none

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