Explain relevance of data dictionary in a database system, Database Management System

Assignment Help:

Explain the relevance of Data Dictionary in a Database System?

Data dictionary is a database in its own right residing on the disk that consist of Meta data which is = Data about all entity sets + attributes + relationships between entity sets + constraints. It consists of compiled creates of definitions, structure and usage information on data stored, design decisions, application programme descriptions, usage standards, user information. It is consulted through DBMS before DML operation and through user to learn what each piece of data and several synonymous of data fields mean. Data dictionary can be integrated system whereas it is element of DBMS or add ons to DBMS. In integrated system data dictionary holds information concerning external, conceptual and internal level of data base. Both in source and object form. It contains source code of each data field value, frequency of its use, audit trail concerning updates and cross reference information. Present system is all add ons standards do not exist for integrity data dictionary along with DBMS. Data dictionary should be integrated in database it describes and therefore involves its own definition so that it can be queried with the similar language use for queering database.


Related Discussions:- Explain relevance of data dictionary in a database system

What are the properties in a relation, What are the properties in a relatio...

What are the properties in a relation ? In a relation Ordering of rows is immaterial and No two rows are identical.

Data redundancy, Data Redundancy -A lot of information is being repeated in...

Data Redundancy -A lot of information is being repeated in the relation. For instance, the information that MCS-014 is named SSAD is repetitive, address of Rahul is "D- 27, Main ro

Extended star schema, Why did SAP introduce the extended star schema? Expla...

Why did SAP introduce the extended star schema? Explain why it is reported to be better than the traditional schema model?

Why do so various organizations use mysql, Why do so various organizations ...

Why do so various organizations use MySQL? Advantages: Open source Highly efficient Offers a high scalability in terms of size and connectivity. Highly prote

Transaction states, The following variant of the primary copy asynchronous-...

The following variant of the primary copy asynchronous-update replication protocol has been proposed for totally replicated systems. (a)  A transaction executing at site A updat

What is called a query evaluation plan, What is called a query evaluation p...

What is called a query evaluation plan? A sequence of primitive operations that can be used to assess a query is a query evaluation plan or a query implementation plan.

ERD, A student entity type has the following attributes,name..

A student entity type has the following attributes,name..

Explain the check clause, Explain the Check Clause The CHECK clause is ...

Explain the Check Clause The CHECK clause is employed to at the end of a CREATE TABLE statement specify table constraints. This is known as table-based constraint because it ap

Define rule that value of foreign key appear in other table, Determine the ...

Determine the rule that a value of a foreign key should appear as a value of some particular table is called a  Ans: Referential constraint.    The rule that a value of a fo

Guidelines for creation of table, Guidelines for creation of table: ...

Guidelines for creation of table: Table name should begin with an alphabet. In table name, single quotes and blank spaces are not allowed. Reserve words of that DBM

Write Your Message!

Captcha
Free Assignment Quote

Assured A++ Grade

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!

All rights reserved! Copyrights ©2019-2020 ExpertsMind IT Educational Pvt Ltd