1. A method for generating test data for testing an application from a database having a table comprising at least one column, the method comprising: receiving a test data query that specifies at least one selection parameter; identifying a data domain associated with the at least one selection parameter, the data domain corresponding to a column in the table and including for each unique value in the column a corresponding unique entity identifier; automatically generating an entity selection map that identifies one or more entity identifiers included in the data domain, each of the one or more entity identifiers satisfying the at least one selection parameter; automatically generating a test data definition associated with the test data query based on the entity selection map, the test data definition identifying test data in the database associated with the one or more entity identifiers; and automatically executing the test data definition to extract the test data.