Databases

Table of Contents

Joins

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Joins

Types:

[INNER] JOIN: usual join, eliminates tuples without a partner
LEFT JOIN: preserves rows of left table
RIGHT JOIN: preserves rows of right table
FULL JOIN: preserves rows of both tables
CROSS JOIN: Cartesian product in all combinations

Join predicates:

NATURAL: yields comparison of columns with same name
USING (A1, ..., An) appended