Cognos report studio joins

[barrysaab]

how to understand cognos report studio joins where it is easy to understand in oracle
for example below seems to me like equi join where as cognos says it is outerjoin,Appreciate if somone could explain how to interpret cognos joins easily
[Customer_Traffic_Query].[Calendar Date] = [Date_Org_Query].[Calendar Date] and

[Customer_Traffic_Query].[Organization Code] = [Date_Org_Query].[Organization Code]

[blom0344]

both inner and outer joins are equi-joins. In Cognos you use cardinalities to:
1. Define whether join type is inner / outer
2. Define cardinality as  1:1 / 1:n etc

In ANSI notation (and any other) only the first property is expressed:

Inner join

Code Select Expand


SELECT ....
FROM TABLE_A  A
INNER JOIN
TABLE_B B
ON A.X = B.Y


Left outer join:

Code Select Expand


SELECT ....
FROM TABLE_A  A
LEFT OUTER JOIN
TABLE_B B
ON A.X = B.Y


But both are essential  equi-joins , as opposed to the theta-join:

Code Select Expand


SELECT ....
FROM TABLE_A  A
LEFT OUTER JOIN
TABLE_B B
ON A.X < B.Y


The second property relating to cardinality is NOT expressed in the join syntax, but used by Cognos to determine dimension - fact relationship. There is AFAIK no mechanism that would exist within Oracle (or any other DB)