What are the purpose for having variable length records, Database Management System

Assignment Help:

What are the purpose for having variable length records? What kinds of separator characters are required for each?

Variable-Length Records - Variable-length records are those records that are of various sizes. A file may holds variable-length records in any of the subsequent situations:

• Records having variable length fields - In this case, the end-of-field symbol along with end-of-record symbol could be used as the separator characters.

• Records having repeating fields - In this case, the number of repetitions of repeating area can be used along with end-of-record symbol as the separator characters.

• Records having optional fields - In this case, the end-of-field symbol along with end-of-record symbol could be used as the separator characters.

• File containing records of various record types - In this case, a special field (or control field) can be prefixed with every record and end-of-record symbol could be used as the separator characters.

In each of the above situations either we can use end-of-record symbol or the length of every record can be prefixed at the starting of the record for the separation of the variable-length records.


Related Discussions:- What are the purpose for having variable length records

Textbook ordering system, Question: Consider the following database rel...

Question: Consider the following database relations for a textbook ordering system used by a college bookshop: Book (b-copy#, bname, ISBN#, author, price, subject) Order (s#

Explain the aggregation implies concurrency, Explain the Aggregation implie...

Explain the Aggregation implies concurrency Concurrency actually is: This in objects can be identified by the way they change state. Present objects can change state independen

Explain the relational completeness, Explain the Relational Completeness ...

Explain the Relational Completeness Codd described the term relational completeness to consider to a language that is complete with respect to first-order predicate calculus ex

Explain function group, What is a function group? A function group is ...

What is a function group? A function group is a collection of logically related modules that share global data with every other.  All the modules in the group are contained in

I need automated trading engine for crypto currencies, Project Description:...

Project Description: Looking to prepare automated trading engine for alternate cyprto currencies starting with Cryptsy, finally integrating into other exchanges. Need to work wi

Define hash files organization, Define Hash files organization a. Hashi...

Define Hash files organization a. Hashing includes computing the address of a data item by calculating a function on the search key value.   b. A hash function h is a functi

Increased overheads on update-data replication, Increased overheads on upda...

Increased overheads on update : On the drawbacks side, it will need the system to ensure that all replicas of a relation are consistent. This shows that all the replicas of the rel

Describe the nested-loop join and block-nested loop join, Describe the nest...

Describe the nested-loop join and block-nested loop join.   Ans:   The block nested- loop join algorithm is as described below:     for every block B r of relation R do beg

Explain derived and non-derived attribute, Explain Derived and Non-Derived ...

Explain Derived and Non-Derived Attribute? In few cases, two or more attribute values are related, for instance, Age and BirthDate attributes of a person. For specific person e

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