SQL SELECT: Difference between revisions

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Table alias.
Table alias.


===Multiple Tables===
===Querying Multiple Tables===
{{Internal|SQL_Querying_Multiple_Tables#Overview|Querying Multiple Tables}}
{{Internal|SQL_Querying_Multiple_Tables#Overview|Querying Multiple Tables}}



Revision as of 21:09, 22 May 2024

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.

Querying Multiple Tables

Querying Multiple Tables

WHERE

Filters, conditions, condition evaluation.

GROUP BY ... HAVING

(make sure I understand thoroughly and link)

ORDER BY