SQL SELECT

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Internal

Overview

Query execution. SQL optimizer. Subqueries.

SELECT FROM WHERE GROUP BY HAVING ORDER BY 

Select all (possibly across multiple tables) then filter and discard with where.

Clauses

=FROM

FROM permanent|derived|temporary|virtual(view)

Table alias.

Multiple Tables

Link here. Joining Tables.

=WHERE

Filters, conditions, condition evaluation.

GROUP BY ... HAVING

(make sure I understand thoroughly and link)

ORDER BY