Unlike an inner join, it also returns unmatched rows: LEFT OUTER and RIGHT OUTER keep those from one table, FULL OUTER from both, and columns with no counterpart come back as NULL.
Read more: Microsoft Learn
In the Ultra Transcenders books
Each book explains Outer join in context, with comparison tables and the common traps.
Terms in this definition
- JOIN
Combines rows from two or more tables in one SELECT, most often by pairing a primary key with the foreign key that refers to it.
- RETURNS
States what a function gives back, as a type or a table, inside
CREATE FUNCTION. SQL functions can leave it out and have the type worked out from their body. - Event
Table in Log Analytics where entries from Windows event logs are kept.
- NULL
Marks that a row has nothing in a particular column, as when a person has no middle name. Columns defined NOT NULL can never be left empty.
Related terms
- APPLY
Evaluates a table-valued expression for every row on its left, inside
FROM. Think ofOUTER APPLYas a left outer join andCROSS APPLYas an inner join.