A method and system presents an online reorganization of at least a portion of a database. The database includes a plurality of rows stored in a plurality of physical blocks and the rows are categorized by a plurality of reference groups. The database manager is operable to identify a target subset of physical blocks based, at least in part, on one of the reference groups and to identify a source subset of physical blocks associated with the particular reference group. The database manager is further operable to dynamically move the rows stored in a first physical block in the source subset to a second physical block in the target subset while the database is online.