Skip to main content

Normalization -- PDF Download




Normalization


Labels:

Comments

Smruti said…
Hi Sir Please give me the answer

Why we use @@ symbol in oracle
or difference between @ and @@
October 18, 2011 at 1:52 PM
Smruti said…
Hi Sir Please give me the answer

Why we use @@ symbol in oracle
or difference between @ and @@ ?


Please change the back ground color of the site from black to whit and letter color to white so the site is more eye catching.
October 22, 2011 at 12:51 AM
Mithun Ashok said…
Hi Smruti,

Refer to the link below for the difference,

Difference between @ and @@

Problem with white text is its too flashy, so I usually use them for sql statements or to highlight some text on my site.

Nevertheless will change my sites theme completely in some time. :-)

Regards,
Mithun
October 22, 2011 at 9:08 AM
baba said…
everything in the world is with some special trait
imbued
god has taught music sweet to the speechless birds
and god has sent mithun to teach sql
your teaching is multicolored,multifaceted flashing different hues
your teaching is like beacon light that is guiding students to their goal
your teaching has made a mark on everybodys heart
and people in large number enjoy your teaching
immortal are the merits of your teaching
October 23, 2011 at 10:51 PM
Post a Comment

Popular posts from this blog

SQL Interview Questions on Subqueries

SUB Queries:
1. List the employees working in research department 2. List employees who are located in New York and Chicago
3. Display the department name in which ANALYSTS are working
4. Display employees who are reporting to JONES
5. Display all the employees who are reporting to Jones Manager
6. Display all the managers in SALES and ACCOUNTING department
7. Display all the employee names in Research and Sales Department who are having at least 1 person reporting to them
8. Display all employees who do not have any reportees
9. List employees who are having at least 2 reporting
10. List the department names which are having more than 5 employees
11. List department name having at-least 3 salesman
12. List employees from research and accounting having at-least 2 reporting
13. Display second max salary
14. Display 4th max salary
15. Display 5th max salary  -- Answer for nth Max Salary
Co-Related Subqueries:
16. Write a query to get 4th max salary from EMP table
17. Write a query to get 2nd…
21 comments
Read more

'Linux-x86_64 Error: 28: No space left on device' While trying to start the database -- Error

SQL> startup mount pfile='/tmp/initdlfasp12.ora'
ORA-27102: out of memory
Linux-x86_64 Error: 28: No space left on device


This as you can see is on Linux x86 with 64 bit processor. We got this error after we changed SGA on 10gR2 database. So was sure that this is something to do with the OS.

Parameters to check for this are shmall.

shmall is the total amount of shared memory, in pages, that the system can use at one time.

$cat /proc/sys/kernel/shmmax
53687091200

$ getconf PAGE_SIZE
4096

As per Oracle SHMALL should be set to the total amount of physical RAM divided by page size.

Our system has 64GB memory, so change kernel.shmall = 1024 * 1024 * 1024 * 64 / 4096 = 16777216


Once this value is calculated you can modify Linux system configuration file directly.

$ su - root
vi /etc/sysctl.conf file:
kernel.shmall=16777216

and

# sysctl -p

Once this is done the database was started without any problem.
13 comments
Read more

Answers for SUB Queries

1. SQL> select empno, ename from emp where deptno=(select deptno from dept where dname='RESEARCH');


2. SQL> select empno, ename from emp where deptno in (select deptno from dept where loc in ('NEW YORK','CHICAGO'));

3. SQL> select dname from dept where deptno in ( select deptno from emp where job ='ANALYST');

4. SQL> select empno, ename, mgr from emp where mgr = (select empno from emp where ename='JONES');

5. SQL> select empno, ename, mgr from emp where mgr = (select mgr from emp where ename='JONES')

6. SQL> select empno, ename, job from emp where deptno in ( select deptno from dept where dname in ('SALES','ACCOUNTING'))

7. SQL> select empno, ename, job from emp where deptno in ( select deptno from dept where dname in ('SALES','RESEARCH')) and empno in (select mgr from emp)

8. SQL> select empno, ename from emp where empno not in ( select mgr from emp where mgr is not null)

9. select…
8 comments
Read more