Data Management:
The Data management component stores as well as retrieves sets of records. It implements the objects- set of records, network, cursor, record, field and view.
Records and fields:
A record type is a sequence of field types as well as a record instance is a corresponding sequence of field instances. Record types as well as instances are persistent objects. The record instances are the atomic units of insertion as well as retrieval. Fields are sub-objects of records as well as are the atomic units of update. Fields contain the attributes of atoms (example FIXED(31)or CHAR(*)) and field instances have atomic values (Example “3” or “BUTTERFLY”). Every record instance has a unique name called a record identifier (RID).
A field type constrains the type as well as values of instances of a field and defines the representation of such instances. The record type identifies what fields take place in instances of that record type.
A usual record might have ten fields and occupy 256 bytes although records often have hundreds of fields (example a record giving statistics on a census tract has over 600 fields), as well as may be very large (several thousand bytes). A extremely simple record (nine fields and about eighty characters) might be described by:
DECLARE 1 PHONE_BOOK_RECORD,2 PERSON_NAME CHAR(*),2 ADDRESS,3 STREET_NUMBER CHAR(*),3 STREET_NAME CHAR(*),3 CITY CHAR(*),3 STATE CHAR(*),3 ZIP_CODE CHAR(5).2 PHONE_NUMBER,3 AREA_CODE CHAR(3),3 PREFIX CHAR(3),3 STATION CHAR(4);
The operators on records comprises INSERT, DELETE, FETCH and UPDATE. Records are able to be CONNECTED to and DISCONNECTED from membership in a set (see below). These operators in actuality apply to cursors which in turn point to records.
The notions of record as well as field correspond very closely to the notions of record and element in COBOL or structure and field in PL/l. Records are variously denoted as entities, tuples, segments and rows by different subcultures. Most systems have alike notions of records although they may or mayn’t support optional fields (nulls), variable length fields or repeated fields.
Latest technology based Operating System Online Tutoring Assistance
Tutors, at the www.tutorsglobe.com, take pledge to provide full satisfaction and assurance in Operating System help via online tutoring. Students are getting 100% satisfaction by online tutors across the globe. Here you can get homework help for Operating System, project ideas and tutorials. We provide email based Operating System help. You can join us to ask queries 24x7 with live, experienced and qualified online tutors specialized in Operating System. Through Online Tutoring, you would be able to complete your homework or assignments at your home. Tutors at the TutorsGlobe are committed to provide the best quality online tutoring assistance for Operating System Homework help and assignment help services. They use their experience, as they have solved thousands of the Operating System assignments, which may help you to solve your complex issues of Operating System. TutorsGlobe assure for the best quality compliance to your homework. Compromise with quality is not in our dictionary. If we feel that we are not able to provide the homework help as per the deadline or given instruction by the student, we refund the money of the student without any delay.
tutorsglobe.com assumptions of short-run law assignment help-homework help by online classification of production function tutors
contingency tables tutorial all along with the key concepts of chi-square distribution, properties of chi-square, chi-square testing, chi-square testing procedure
theory and lecture notes of regular expressions all along with the key concepts of regular expressions, finite automata and regular languages, warshall and floyd algorithm, closure of the class of regular sets, state minimization. tutorsglobe offers homework help, assignment help and tutor’s assistance on regular expressions.
tutorsglobe.com properties of copper assignment help-homework help by online occurrence and principles of extraction of copper tutors
tutorsglobe.com chemosynthesis assignment help-homework help by online plant physiology tutors
tutorsglobe.com properties of lead assignment help-homework help by online lead tutors
tutorsglobe.com characteristics of capital assignment help-homework help by online capital tutors
www.tutorsglobe.com offers object oriented paradigm homework help, assignment help, case study, writing homework help, online tutoring assistance by computer science tutors.
tutorsglobe.com rent-marginal-wages theory of profit assignment help-homework help by online theories of profit tutors
Main Components of the vacuum cleaner: There are six main components to a standard vacuum cleaner.
www.tutorsglobe.com offers system fundamentals homework help, system fundamentals assignment help, case study, writing homework help, online tutoring assistance by computer science tutors.
Chemical Kinetics tutorial all along with the key concepts of Factors that affect Reaction rates, Reaction Rates, Rate Laws, Units of rate constant and rate law from experimental data
tutorsglobe.com neo-darwinism assignment help-homework help by online darwinism tutors
online gre exam preparation course and online gre tutoring package offered by TutorsGlobe are the most comprehensive and customized collection of study resources on the web, offering best collection of gre practice papers, quizzes, gre test papers, and guidance.
tutorsglobe.com prevention of hiv assignment help-homework help by online emerging viral infections in humans tutors
1934318
Questions Asked
3689
Tutors
1468162
Questions Answered
Start Excelling in your courses, Ask an Expert and get answers for your homework and assignments!!