What are primary keys and foreign keys, Computer Engineering

Assignment Help:

What are primary keys and foreign keys?

Primary keys are the unique identifiers for every row. They must have unique values and cannot be null. Due to their significance in relational databases, Primary keys are the most fundamental of all keys and constraints. A table can have only one Primary key. Foreign keys are both a method of ensuring data integrity and a manifestation of the relationship among tables.

 


Related Discussions:- What are primary keys and foreign keys

Explain data mining, Data Mining is an analytic method designed to explore...

Data Mining is an analytic method designed to explore data and then to validate the findings by applying the detected patterns to latest subsets of data.  The ultimate goal of dat

Forall statement in fortran, Q. FORALL Statement in fortran? The FORALL...

Q. FORALL Statement in fortran? The FORALL statement permits for more common assignments to sections of an array. A FORALL statement has general form.   FORALL ( triplet, ..

Explain the differences between macros and subroutines, Explain the differe...

Explain the differences between macros and subroutines. Macros Vs Subroutines (i) Macros are pre-processor directives which are processed before the source program is pass

Example of finding cross points and switches, For a non blocking crossbar c...

For a non blocking crossbar configuration, taking N as the number of subscribers, there will be               number of cross points and _             number of switches for est

Explain the term- tracker ball and braille printers, Explain the term- Trac...

Explain the term- Tracker ball and Braille printers Tracker ball Easier to use than a mouse if people have problems using their arms and hands or if they have a coordinati

Information system for strategic advantage, Q. Describe short note on Infor...

Q. Describe short note on Information system for strategic advantage? Ans. Strategic role of information systems engage using information technology to develop products or serv

What happens to logic after synthesis, What happens to logic after synthesi...

What happens to logic after synthesis, which is driving an unconnected output port that is left open (, that is, noconnect) during its module instantiation? An unconnected out

What are the components of loadrunner, The workings of LoadRunner are The V...

The workings of LoadRunner are The Virtual User Generator, Controller, and the Agent process, LoadRunner examines and Monitoring, LoadRunner Books Online. What Component of LoadRun

What is called when a program is in execution, A program in execution is ca...

A program in execution is called?  Ans. When a program in execution is known as Process.

Write an html program segment that contains hypertext links, Write an HTML ...

Write an HTML program segment that contains hypertext links from one document to another . HTML permits any item to be placed as a hypertext reference. Therefore a single word

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