Define a relation schema, Database Management System

A Relation Schema represented by R(A1, A2, ..., An) is made up of the relation name the list of attributes and R Ai that it contains. A relation is described as a set of tuples. Let r be the relation which have set tuples (t1, t2, t3, ..., tn). Each tuple is an ordered list of n-values t=(v1,v2, ..., vn).

The purpose of the relational model is to give a declarative function for specifying queries and data: users directly state what information the database have and what information they want from it, and let the database management system software take care of explain data structures for retrieval procedures and storing the data for answering queries.

 

1225_Relational Schema.png

Posted Date: 7/30/2012 1:52:29 AM | Location : United States







Related Discussions:- Define a relation schema, Assignment Help, Ask Question on Define a relation schema, Get Answer, Expert's Help, Define a relation schema Discussions

Write discussion on Define a relation schema
Your posts are moderated
Related Questions
Deadlock Prevention One of the easiest approaches for avoiding a deadlock would be to obtain all the locks at the begin of the transaction. Though, this approach restricts conc

Explain the dependency relationship of object oriented A dependency is a relationship which states that a change in specification of one thing can affect another thing, but n

What is recursive closure? Why is it not possible to describe this operation in relational algebra? Recursive closure is applied to recursive relationship. An instance of rec

What are the three types of data sources used with ODBC? An ODBC file data source is a file that can be shared between database users. An ODBC system data source is one that is

Describe the storage structure of indexed sequential files and their access method. Ans: Index offers a lookup capability to rapidly reach the vicinity of the desired record.

The following relational database schema represents part of a simplified database used by a library: tblBook (BookID, Title, PublisherID, Category,Price) tblPublisher (Publishe

Problem 1 Why are the operational system keys not recommended for forming data warehouse primary keys? Give any two examples 2 Explain the following performance tuning techn

DDL Compiler The DDL compiler changes the data definition statements (such as CREATE TABLE .... in SQL) into a set of tables having metadata tables. These tables have infor

What are the time stamps associated with each data item? W-timestamp (Q) denotes the largest time stamp if any transaction that implemented WRITE (Q) successfully. R-timesta

how to make an e r diagram?