What is the difference between JOIN and UNION?

What is the difference between JOIN and UNION?

sql database join union

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select max, min values from two tables

sql database select union

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MySQL: looking to SUM these UNIONs together

mysql database union

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View over multiple tables containing same columns

sql database union

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SQL - JOIN using UNION ?? UNION using JOIN?

sql database join union

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Combine two mysql query into one

php mysql sql database union

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MySQL - Searching with UNION ALL and GROUP BY

sql mysql database group-by union

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Are these two relations compatible for a union operation?

database relational-database union relational-algebra

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union query in access too complex for evaluation

sql database union

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