Arcadia Enterprise supports five types of column connections, otherwise known as joins: inner, left, right, outer, and left outer joins.
FULL OUTER JOIN
operations.FULL OUTER JOIN
and
RIGHT OUTER JOIN
operations.In an inner join, the most common type, rows in the result set contain the requested columns from the both tables for all combinations of rows where the selected columns of the tables have identical values.
In a left join, the result set contains all rows from
the left-hand table, and the matching data from the right table. Whenever no matching data
is available on the right side of the join, the corresponding columns in the result set
have the value NULL
.
In a right join, the result set contains all rows
from the right-hand table, and the matching data from the left table. Whenever no matching
data is available on the left side of the join, the corresponding columns in the result
set have the value NULL
.
An outer join returns all rows from both tables.
Whenever no matching data is available on one of the sides of the join, the corresponding
columns in the result set have the value NULL
.
A special case, left outer join, supports join elimination in datasets that contain more than one table. By default, this setting is on, but it can be disabled. See Join Elimination.