A data generator for database schema verification, system sizing and functional test of data dependent applications. Allows for generation of data from random values or from working databases which may be profiled to generate patterns for occurrences of values and sizes of values. The data may be filled with a fill rate that dictates the percentage of fields assigned nulls. Cardinality allows for a fixed number of values to occur across the records for a field. May utilize reference data associated with an existing database to fill fields. Qualifiers and multi-value fields may be filled to mimic real data. Maximum, nominal and average number of occurrences of sizes of data and qualifiers and multi-value data may be specified. May also utilize dictionaries to fill. Hierarchical levels and number of child nodes may also be specified and used in filling taxonomy tables and hierarchy tables for example.