SQL: Difference between revisions

From NovaOrdis Knowledge Base
Jump to navigation Jump to search
(7 intermediate revisions by the same user not shown)
Line 1: Line 1:
=External=
* [https://learning.oreilly.com/library/view/learning-sql-3rd/9781492057604 Learning SQL, 3rd Edition] by Alan Beaulieu
=Internal=
=Internal=
* [[Relational Databases]]
* [[Relational Databases]]
Line 5: Line 8:


=Overview=
=Overview=
This article documents standard SQL. For database-specific extensions, we'll link to the databases-specific DML operations page.


=JOIN=
SQL is a non-procedural language <font color=darkkhaki>TODO: [https://learning.oreilly.com/library/view/learning-sql-3rd/9781492057604/ch01.html#sql_colon_a_nonprocedural_language this]</font>
 
The SQL <code>JOIN</code> clause is used to combine rows from two or more tables, based on a related column between them.
 
==INNER JOIN==
Return records that have matching values in both tables.
==LEFT (OUTER) JOIN==
Return all records from the left table and the matching records from the right table.
==RIGHT (OUTER) JOIN==
Return all records from the right table and the matching records from the left table.
==FULL (OUTER) JOIN==
Returns all records when there is a match in either left or right table.

Revision as of 20:39, 22 May 2024

External

Internal

Overview

This article documents standard SQL. For database-specific extensions, we'll link to the databases-specific DML operations page.

SQL is a non-procedural language TODO: this