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Questions from Qspiders


(1) How do I list all of my tables?

(2) Create one table from another table without copying the data from the first table.

(3) How do I select from different user’s tables?

(4) What is SQL?

(5) What is a function in oracle?

(6) What is the default format of date in Oracle? How can I change my default date format?

(7) Difference between
a)     ROLLBACK & SAVEPOINT
b)     ROLLBACK & COMMIT
c)      Truncate & Delete
d)     Truncate & Drop
e)     Delete & Drop
f)      PK and (UNIQUE + Not Null)
g)     ROUND & TRUNC
h)     ROWID & ROWNUM
i)        Alternate Key & Candidate Key
j)       Simple Key & Composite Key
k)     Stored Procedure and Function
l)        Stored Procedure and Trigger
m)   Equi-Join and Outer Join
n)     CHAR & VARCHAR2
o)     CASE Statements & DECODE
p)     UNION and UNION ALL

8) What is a view? What are its advantages?

9) What is a synonym?

10) What is PL/SQL?

11) What is an Index? Why it is useful?

12) What is PL/SQL?

13) Mention some features of Oracle 9i database.

14) Mention some features of Oracle 10g database.

15) What is the meaning of “i” and “g” in 9i & 10g respectively?

16) What is the purpose of joining the tables? Explain different types of Joins.

17) What are the data types available in Oracle? Explain.

(18) What is Database Link?

(19) What is Tuning? Explain.

(20) What is DDL? Give examples.

(21) What is DML? Give examples.

(23) What is the difference between DBMS & RDBMS?

(24) State some of the Codd Rules.

(25) What is normalization? Explain.

(26) Few differences between Oracle and SQL Server databases.

(27) What is a Sequence?

(28) Write a query to eliminate duplicates rows from a table?

(29) How does one implement IF-THEN-ELSE in a select statement?

(30) How we can send the query output to a file?

(31) Display the Department Names that are having more than 4 employees in it?

(31) What is SQL* Loader?

(32) What is Export & Import?

(33) Increase the salaries of all the employees by 10% for the departments that are common in both of these tables.

Table1



Deptno
Empno
Sal
10
1
1000
10
2
3000
20
3
2000
30
4
6000
20
5
1000
60
6
9000
10
7
1000


Table2



Deptno

10
40

(34) Write the syntax to add Foreign Key?

(35) Write the syntax to create Composite Primary Key?

(36) How to run the SQL statements from a file?

(37) What is a schema?

(38) What are DCLs?

(39) What are roles & privileges?

(40) What are sub query statements and co-related sub query statements?

Comments

sam said…
Sir,I want all the answers for questions from qspider -----sam
Payal Prajapati said…
Hello Sir,
Plz post the answers for Qspider questions based on queries.
Ritesh Jha said…
sir pls provide answers for question 1 and 3.
This also not given in your class
Sona Naidu said…
This comment has been removed by the author.

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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');

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

9. select…

'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.