The entity profile discovers entity relationships in the source data. An entity consists of related parent and child tables. The entity profile returns a list of possible entities by comparing column names in the source tables. You can select entities from the profile results to add to the project. When you run a data subset operation, the entities that you define for the subset determine the subset database structure and the data in the subset.
For example, the Employee table, the Employee_Detail table, and an Employee_Address table contain an EmpID column. The entity profile suggests that the Employee table could be an entity with two direct relationships. The Employee table has two child tables. When you view the profile results, you select the Employee table as an entity. When you run a data subset operation, you can create a filter on EmpID to retrieve the data for employees with an EmpID less than 2000. The data subset operation filters data for each table in the entity relationship.
If you select Entity as the profile type, and the physical database does not contain primary keys, the profile does not return any results. If you run the profile as a primary key and entity profile, the profile discovers possible primary keys and foreign keys. The profile returns results even if the physical database does not contain primary keys.