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References to DBMS Concepts

Many of you may have some concern on Basics of DBMS and about the definitions of R-DBMS, H-DBMS and N-DBMS. Some of you might have studied the concepts little different than the one I have defined on my site, but nevertheless definitions and concepts(DBMS) on my site are simple and easy to understand which are explained at a very basic level. Am collating some links which will provide similar and more detailed definitions and insight on DBMS concepts.

DBMS and its history --
Types of DBMS --
Notes from Penn State University, USA --
Flat File Database --
Hierarchical DBMS --
Network DBMS --
Relational DBMS --
Database(Do not get confused with so much information, treat this link as a reference) --

Hope this clears the confusion in air.


rashmi dhiman said…
hello sir....i want a suggestion from u,can i do manual testing and QTP together...will it effect my study or any other loss???
Mithun Ashok said…
Hi Rashmi Dhiman,

If you want you can take do both Manual and QTP together only thing is you have to put in lot of effort and concentrate on both the topics.

It is suggested to take these courses one after the other so you get enough time to study.

TEJ said…
I'm looking for enotes of complete SQL notes.

Plz guide me as to which is the best book to refer!

With regards,
Tej G.K
Mithun Ashok said…
Hi Tej,

Follow the link below,

TEJ said…
Hi Mithun,

Thank you :)

With regards,
Tej G.K
TEJ said…
Hi Mithun,

I have small confusion between ROUND and TRUNC operator's.

Can you tel me the answers for the following qn's are right or wrong .
ROUND( 1742.471,-1) -> 1740
ROUND( 1742.471,-2) -> 1700
ROUND( 1742.471,-3) -> 2000

TRUNC( 1742.471,-1) -> 1740
TRUNC( 1742.471,-2) -> 1700
TRUNC( 1742.471,-3) -> 1000

Let me know if any answers wrong and explanat it plz.
Sir, Plz tell us that what would be the series of initial 5 questions that u would be asking in an inrterview ??
Plz tell us that what would be the initial 5 questions that u yould b asking in an interview on SQL .
Mithun Ashok said…
Hi Tej,

Execute these number functions and let me know if you have any queries.

Mithun Ashok said…
Hi Harish,

Will write an article on this gimme some time.

naresh n said…
hello sir........ i installed oracle that i entered password(system) and thre not asking any username by during installation....after completing sucessful installation its asking username also what can i do now...........?
Mithun Ashok said…
Hi Naresh,

Use scott as username and tiger as password.

Usha.V said…
Hi sir:) we have to display name,hire date,day of the week on which the emp started n order bt the day of the week starting with monday.
i wrote the query as:
SELECT ename,hiredate,to_char(hiredate,'DAY')as day
FROM emp
ORDER BY day=to_char(hiredate,'MONDAY');
but im nt getting the desired result. wht changes shld i do sir
Smruti said…
Hi Sir Please give the bellow questions answers.

What is the difference between trigger and constraint? Give more than five difference
Mithun Ashok said…
Hi Usha,

Refer to the article below,

Sorting by day of the week

Mithun Ashok said…
Hi Smruti,

Triggers are used to execute some procedure in case of database events.

Constraint are the restrictions that you can have on each column.

vamshi said…
hii sir, i have to learn some basics of pl/Sql and oracle apps for that what all is the basic knowledge required and can u mail me some useful material for this since i din't find in this site
wish you a very very happy deepawali sir.....
uday said…
wish you a very very happy deepawali sir....
Amit Jha said…
i found this on internet...hope it will be useful for you...""
Dipan saha said…
Sir i am confuse about DBMS and RDBMS.Please tell me the different
deepak r said…
Mithun sir u are awesome, awesome teaching, interactive blog... great
saket singh said…
sir somehow meanwhile installation sql plus i missed unlocking in the username & password field what should i enter to access the s/w.......plz recommend me some suggestions

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