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What is the difference between a sub query and a join? Under what circumstances would you not be able to use a sub query?

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With a sub query, the columns specified in the SELECT list are restricted to one table. Thus, cannot use a sub query if the SELECT list contains columns from more than one table

kevowmuchiri answered the question on July 4, 2018 at 15:42

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Next: Explain how the GROUP BY clause works. What is the difference between the WHERE and HAVING clauses?

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