0 votes 0 votes External schema consists of: a) Subschemas b) Virtual Tables c) Both a and b d) None of these Databases databases + – sh!va asked Apr 27, 2017 sh!va 266 views answer comment Share Follow See all 0 reply Please log in or register to add a comment.
0 votes 0 votes According to me d answer should be b) Virtual Tables which in turn r nothing but views. :) In database theory, a view is the result set of a stored query on the data, which the database users can query just as they would in a persistent database collection object. This pre-established query command is kept in the database dictionary. Unlike ordinary base tables in a relational database, a view does not form part of the physical schema: as a result set, it is a virtual table computed or collated dynamically from data in the database when access to that view is requested. Devshree Dubey answered Apr 27, 2017 Devshree Dubey comment Share Follow See all 0 reply Please log in or register to add a comment.