Database Design: This comprises logical (that is, entity relationship) and physical (that is, table, column and key) design tools for the data. Physical data modeling is becoming approximately mandatory for applications employing relational database management systems (abbreviated as RDBMSs). Strong support for the physical modeling is paired with facilities to administer manifold models, to sub model or extract from bigger models, and to reverse-engineer a database design from recognized tables. The Data architects or analysts and database designers or administrators are the main targeted users of such tools, though developers are a secondary market frequently targeted with a subset of the total functionality.