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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
c)      Truncate & Delete
d)     Truncate & Drop
e)     Delete & Drop
f)      PK and (UNIQUE + Not Null)
g)     ROUND & TRUNC
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.






(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?


sam said…
Sir,I want all the answers for questions from qspider -----sam
Unknown said…
Hello Sir,
Plz post the answers for Qspider questions based on queries.
Unknown 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.
rohit said…
OK thanks for this post it's quite informative and I have learned new things.

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1. SQL> SELECT empno, ename FROM emp WHERE Length(ename) = 4;

2. SQL> SELECT empno, ename, job FROM emp where Length(job)=7;

3. SQL> SELECT Length('qspiders') - Length(replace('qspiders','s','')) FROM dual;

4. SQL>  SELECT empno, ename, job FROM emp WHERE Instr(job,'MAN') >0;

5. SQL> SELECT empno, ename, job FROM emp WHERE Instr(job, 'MAN') =1;

6. SQL> SELECT empno, ename, job FROM emp WHERE (Length(ename) - Length(Replace(ename, 'L',''))) = 1;

7. SQL> SELECT * FROM dept WHERE Instr(dname,'O') > 0;

8. SQL> SELECT Concat(ename,' working as a ') || Concat(job, ' earns ') || Concat(sal, '  in ') || Conc
at('dept ',deptno) AS text from emp;


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