SQL SELECT: Difference between revisions
Jump to navigation
Jump to search
| Line 18: | Line 18: | ||
<syntaxhighlight lang='sql'> | <syntaxhighlight lang='sql'> | ||
SELECT id, name FROM person WHERE id = ; | SELECT id, name FROM person WHERE id = 1; | ||
</syntaxhighlight> | </syntaxhighlight> | ||
Revision as of 22:56, 22 May 2024
Internal
Overview
Upon execution, an SQL query returns a result set.
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.
Example
SELECT id, name FROM person WHERE id = 1;
Clauses
FROM
FROM permanent|derived|temporary|virtual(view)
Table alias.
Querying Multiple Tables
WHERE
GROUP BY ... HAVING
(make sure I understand thoroughly and link)