SQL SELECT

From NovaOrdis Knowledge Base
Jump to navigation Jump to search

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

Subqueries