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SQL Basics: Introduction

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Anonymous said…
Hello mithun,

Now SQL online reference is not worrking ....what is the reason?
March 29, 2011 at 4:24 PM
Anonymous said…
Hello mithun,

Hi, Chandrasehar Here, Now SQL online reference is not worrking ....what is the reason?
March 29, 2011 at 4:25 PM
Mithun Ashok said…
Chandrasehar,

Please check the link again, it works fine.

Regards,
Mithun
March 30, 2011 at 11:58 PM
Rakesh Ram said…
hi mithun, can u tell me some details about, Stored Procedures, and Triggers ?
May 11, 2011 at 11:49 PM
Mithun Ashok said…
Hi Rakesh,

PL/SQL Procedure:

1. Doesn't need to return values but can return value.
2.Stored as a pseudo-code in database i.e. compiled form.
3.Can affect the state of database using commit etc.
4.Cannnot be invoked from SQL statements e.g. SELECT.
5.Procedures are mainly used to process the tasks.


Triggers:

Triggers provide a way of executing PL/SQL code on the occurrence of specific database events.

Oracle enables triggers to be invoked by many events other than table insert, update and delete operations.


Mithun
July 10, 2011 at 11:41 AM
Anonymous said…
Hi iS it possible to download the slides?
July 29, 2011 at 12:05 PM
Mithun Ashok said…
Hi,

No, it is not possible to download the slides.

Mithun
July 31, 2011 at 7:06 AM
Sundar said…
Hi Sir,

Whatever applications either it is MS word / Notepad / C, C++, Java, Perl, .Net / whatever it is... they need to have some database to function right? These don't come under any type of DBMS coz they don't belong to any of the structure (Tree, N/W, Table, Object) right? But still y dont we call them as a DBMS? (even when they don't belong to any type of DBMS). Can u explain in detail?
July 31, 2011 at 5:42 PM
Mithun Ashok said…
Hi Sundar,

You need to understand the definition first, Database is a place where data is stored in an organized format.

DBMS is a program or a software which will give you access to any database.

Word, Excel are File based programs which stores data in files and do not require any language to manipulate the data.

C/C++/.Net etc are purely programing languages used to create programs/softwares/Applications etc. Infact some of the DBMS softwares are built using C/C++. These languages do not require DBMS rather they can only be executed using a compiler.

Hope this is clear.

Mithun
July 31, 2011 at 9:05 PM
Anonymous said…
Hello sir,
Pls explain the definition of identifying relationship and Derived attributes with an example? In given slides example is bit difficult to understand for me. So pls give an simple example……..
August 8, 2011 at 3:31 PM
Mithun Ashok said…
Hi,

Any relationship between a Strong entity and a Week entity is classified as Identifying relationship.

Derived attributes are logical attributes of an entity which can be derived by some means.

Regards,
Mithun
August 12, 2011 at 6:19 AM
neetu singh said…
Hello sir.....with the end of SQL classes 2day i would like to thank you for giving a new definition n dimensions to teaching where non computer science students like me as well as those who have d knowledge r equally benefited.Those who really wanna learn SQL should definitely come 2 u 4 guidance..in nutshell you r an excellent trainer..Thank you for building in confidence in me...
August 17, 2011 at 3:27 PM
Anonymous said…
thankz alot for replying......one more think i want to tell u,i knw ppl like u very less on this earth....we need ppl like u n ANNA HAZAARE who devote their precious time and all life for helping ppl........thankz n keep it up....Sir u rockz everyday...ur students gives u alot of blessings n warm wishes like me ......
August 19, 2011 at 2:17 PM
Mithun Ashok said…
Hi Neetu,

Thanks a lot for such wonderful comments.

Mithun
August 22, 2011 at 12:41 AM
Mithun Ashok said…
Thank you Anonymous. My work is just a drop in the ocean and am still very small compared to Anna Hazare. Wish you all the best and thanks for the wishes.

Mithun
August 22, 2011 at 12:44 AM
Anonymous said…
Hi Mithun, the presentations are down, I am not able to access it. Can you kindly check on this....

I am also sending out a mail to your yahoo id of the screen shot what i am seeing....
August 25, 2011 at 5:42 AM
Mithun Ashok said…
Hi,

There was some problem with the presentations and I have fixed it now.

Pls check.
Mithun
August 25, 2011 at 10:12 AM
pallu said…
hello sir. 'm ur student in q spiders ay 7-9 batch. will u pleas explain the yesterday class once.. bec 'm too confused in what is primary key and foreign key and constrants and what is not null and all pleas explain in todays class... bec so many students are confused so 'm asking
August 27, 2011 at 12:04 PM
pallu said…
Hello sir 'm ur student in q spiders at 7-9 batch. will u pleas explain me yesterday topic in today's class bec so many peoples are confused yesterday so 'm asking... we r confused in what is foreign key master key and primary key and all pleas sir explain us once...
August 27, 2011 at 12:08 PM
RAHUL AGARWAL said…
Sir in my database "default tables" are not present,how can i bring them?
August 30, 2011 at 9:28 AM
Anonymous said…
Sir i want to laptop will u pleas tell me which should i buy........ actually u r using acer.
How its working sir
'm ur student pleas tell me sir
August 30, 2011 at 12:25 PM
Mithun Ashok said…
Hi Rahul,

You should login as user SCOTT and use the default password tiger. This will work if you have installed enterprise edition of 10g or 11g.

Regards,
Mithun
September 4, 2011 at 9:11 PM
Mithun Ashok said…
Hi Anonymous,

Acer is working fine and it has not given me any problem for last 1 year.

If you are planning to install database on your laptop then I would suggest you go for a laptop with DUAL Core CPU and minimum 2GB or 4GB RAM.

Regards,
Mithun
September 4, 2011 at 9:13 PM
RAHUL AGARWAL said…
Sir select * from emp where mgr=null,is not working....,it gives "no row selected",infact any column name=null is giving "no rows selected",how can i find person with no manager?
September 4, 2011 at 10:31 PM
Mithun Ashok said…
Hi Rahul,

mgr=NULL will not work, you should use mgr is NULL. In oracle NULL <> NULL.

Use the following statement,

select * from emp where mgr is null;

Regards,
Mithun
September 4, 2011 at 10:45 PM
Anonymous said…
sir
please go bit slow in the class..

thank you.....
September 5, 2011 at 12:16 PM
PINJI said…
hi mithun sir,
pinji here...
sir,i have a doubt,not related to SQL.Actualy,i have been done engineering from chemical branch 2011 batch,so wlil i get opportunity in software field if i will learn this software testing coach nicely.
thnking you.
September 20, 2011 at 2:22 PM
Mithun Ashok said…
Hi Pinji,

You will if you work hard.

Regards,
Mithun
September 24, 2011 at 6:53 PM
baba said…
hello mithun u r a very good lecturer
your teaching is awesome
September 29, 2011 at 10:50 PM
Mithun Ashok said…
Hi Baba,

Thank you,
Mithun
October 3, 2011 at 1:37 PM
Sahana Jogur said…
hello sir,
may i know the difference between data model and schema?
January 2, 2012 at 3:46 PM
Nirmal said…
sir
please go bit slow in the class..
couldnot understand tuesday(6.3.2012) class.because i am basically b.com stundent
March 6, 2012 at 8:10 PM
Rahul Desai said…
Hi Sir,
am a new student in Q-spiders morning batch...
m following u very well ur teaching is very good
u hv mistaken me as Rajnikant as i sit in d last once wen i came late
March 11, 2012 at 9:24 PM
Sowjanya Kinthada said…
sir please go a bit slow.... morning batch...
July 11, 2012 at 10:35 PM
Harisha said…
Hi Sir,Your Teaching is good but it is very fast. Please give us Notes immediately after Teaching so that we can recollect your words....
July 11, 2012 at 11:50 PM
Priya088 said…
hello sir i have almost complete with manually testing i am attending sql class 2 i am BE E&C with 55% will i get job i am not getting interviews and with filed i need 2 work hard
July 12, 2012 at 1:38 PM
:):) said…
hi sir,

i was able to download the oracle 10 g client, got the SQL tool too...couldn't log in though!. it wasn't authenticating the "scott "and "tiger "as the user name and password.I'm not sure if that's the enterprise edition.
July 13, 2012 at 8:42 PM
Mithun Ashok said…
You have donwloaed only 10g Client. You need to download 10g Enterprise edition server.
July 14, 2012 at 7:49 AM
Mithun Ashok said…
Yes Priya, you need to work hard..
July 14, 2012 at 7:50 AM
Mithun Ashok said…
Sure Harisha.
July 14, 2012 at 7:50 AM
Mithun Ashok said…
Sure Sowjanya
July 14, 2012 at 7:50 AM
maya said…
sir plz give me definition of repository
October 26, 2012 at 3:07 PM
Swetha Suryanarayana said…
Hello sir,
How do I download the PPTs on your blog?
I dont see an option like that here.
Kindly help.


Thanks,
Swetha
November 6, 2012 at 12:52 PM
santosh said…
Hi sir, i m a student of jspiders. and i want to download the ppt's of sql from ur site. plzz suggest me how to get those.
November 28, 2012 at 3:49 PM
Learn Java with Rahul said…
Hii mithun sir
sir first of all i want to thank to u for---that u teaches Sql very well.Being a ECE student I am able to understand all 3 to 4 classes u have taken.
My question to is that............u told server is that machine on which server program is installed(e.g in the context of DB u told DBMS server programs) but in genral there are a lot of softares avialble on each PC which can modify or access date(for example....word can modify dat,media softwares can be used to editing video data.) so is that machine also severs.
or is there any restrictions on softwares to be called a server programs......which programs only called server programs?
thanks
regards
rahul kumar(evening 40'clock batch)
April 29, 2014 at 11:08 AM
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