Already have an account? Get multiple benefits of using own account!
Login in your account..!
Remember me
Don't have an account? Create your account in less than a minutes,
Forgot password? how can I recover my password now!
Enter right registered email to receive password!
Synonyms It allows short names or alternative names for objects.
Example:
CREATE SYNONYM D30
FOR EMPD30;
Now if we give command:
SELECT * FROM D30;
NAME
MINSAL
MAXSAL
AVGSAL
---------------------
------------
-------------
--------------
ACCOUNTING
1300
5000
2916.6667
RESEARCH
800
3000
2175
SALES
950
2850
1566.6667
Mappings between Levels and Data Independence The 3 levels of abstraction in the database do not exist separately of each other. There must be some correspondence, or mapping
What is conceptual schema? The schemas at the view level are known as subschema that describe dissimilar views of the database.
During the deletion of a tuple two cases can happen: Deletion of tuple in relation having the foreign key: In this type of case simply delete the desired tuple. For example, in
What is Relational Algebra? Relational algebra is a Procedural query Language?
By using the delete operation some consisting records can be deleted from a relation. To delete some definite records from the database a condition is also specified based on which
what is meant semantic query optimization? how does it differ from other query optimization techniques?
What is Data dictionary? A data dictionary is a reserved space in a database that is employed to store information about the database itself. A data dictionary may consist o
Explain view in RDBMS? View - A view is a relation (virtual rather than base) and could be used in query expressions, which is, queries can be written by using the view as a re
Define the categories of SQL Statements? 1) Statements that don't return a result set. This statement class includes INSERT, DELETE, and UPDATE. 2)Statements that return
Explain five duties of Database Administrator? 1. DBA administers the three stages of the database and, in consultation along with the whole user community, sets up an defin
Get guaranteed satisfaction & time on delivery in every assignment order you paid with us! We ensure premium quality solution document along with free turntin report!
whatsapp: +91-977-207-8620
Phone: +91-977-207-8620
Email: [email protected]
All rights reserved! Copyrights ©2019-2020 ExpertsMind IT Educational Pvt Ltd