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.
biology tutorial tutorial all along with the key concepts of germ plasm and determination of primordial germ cells, germ cell determination in nematodes, germ cell determination in insects, germ cell migration in amphibians, embryonic germ cells and embryonic stem cells
www.tutorsglobe.com offers Binding Scope and Extent homework help, assignment help, case study, writing homework help, online tutoring assistance by computer science tutors.
tutorsglobe.com food preservation assignment help-homework help by online food microbiology tutors
www.tutorsglobe.com offers alkyl halide occurrence homework help, alkyl halide occurrence assignment help, online tutoring assistance, organic chemistry solutions by online qualified tutor's help.
Just the once the company has made its primary share issue to begin business (generally soon after the company is first created) it might decide to make additional issues of new shares.
ideal gases tutorial all along with the key concepts of properties of ideal gases, kinetic theory assumptions regarding ideal gases, empirical gas laws, combined gas law and equations derived from the ideal gas law
theory and lecture notes of current-voltage relationships all along with the key concepts of influence of drain-source voltage, current-voltage relationships, saturation region and channel length modulation. tutorsglobe offers homework help, assignment help and tutor’s assistance on current-voltage relationships.
tutorsglobe.com herpes virus replication assignment help-homework help by online herpes viruses tutors
Get the best Nonlinear System Assignment Help service from subject matter experts at fair prices and score A++ grades with authentic papers.
www.tutorsglobe.com offers area and volume of plane figures homework help, assignment help, online tutoring assistance, geometry mathematics solutions by online qualified tutor's help.
inherent limitations in accounting, homework help, assignment help by online tutors. get solved accounting questions by tutors.
Varicaps or Varactors are employed for electronic tuning in tuner circuits. Varactor is a unique silicon diode, the junction capacitance of which is employed for tuning.
www.tutorsglobe.com offers go to statement homework help, assignment help, case study, writing homework help, online tutoring assistance by computer science tutors.
The value added statement (VAS) came into existence in the middle 1970s following publication of an influential discussion document that entitled The Corporate Report. The Corporate Report argued for the inclusion of the VAS under the annual report.
Copolymerization tutorial all along with the key concepts of Types of copolymers, Benefits of copolymerization, synthesis of macromolecules
1930995
Questions Asked
3689
Tutors
1448962
Questions Answered
Start Excelling in your courses, Ask an Expert and get answers for your homework and assignments!!