Analyzing Data › Defining Entity Types, Relationships, and Attributes › Defining Relationships › Relationship Pairing Percentage

Relationship Pairing Percentage

For an optional relationship membership, the probability that at least one pairing is likely to exist for a given entity is useful during database design and for projecting the performance of the planned system. You can conveniently gather this information from the business.

For example, assume that 100 customers exist and 95 of them have an outstanding order. The probability of a CUSTOMER being paired with an ORDER based on the places relationship membership is therefore 0.95, or 95.

This can be specified in CA Gen, and by showing the percentage in parentheses, as follows:

• Each CUSTOMER sometimes (95%) places one or more ORDERs
• Each ORDER always is placed by exactly one CUSTOMER

The second membership is mandatory, so it remains unchanged.