Loop:

Loop:

A loop is said to exist when there is more than one “path” of joins between two tables.

If a loop exists between two tables, BusinessObjects will not be able to generate the SQL for a query against the tables; it does not know which “path” to choose

A common type of join path that returns too few rows is called loop (Joins form multiple paths between lookup tables)

Tables depending upon many tables

Dimensional table that depends upon a lookup table forms a loop and in this case we can’t get the expected output (few rows will be returned). Intersection.

Loops problem can be resolved using Aliases, contexts and detecting cardinalities
alias represents the table in a different context.

Loop problem can be resolved by removing a Join

Loop is a Multiple paths between the tables selected in queries. Or you can say loop is a closed path structure.

Loops can be resolved by…

ALIASES Alias - Same as the namesake in SQL.Exact duplicate of the original table.A different name “tricks” the SQL query to accept that you are using 2 different tables.

CONTEXTS• Rule which helps BO decide which of the 2 paths to choose in a loop.

BO prompts the user to indicate the correct perspective (relevant path) for the query.

When to AliasA loop with a single lookup table should be resolved by an aliasA lookup table can be identified by its cardinality A lookup table only has the ‘one’ end of joins attached to it