Databases Interview Questions, Answers for Freshers and Experienced asked in various Company Job Interviews

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Databases Interview Questions

Questions Answers Views Company eMail

select trunc(round(156.00,-1),-1) from dual;

2 31267

hi,i plan to put experience on PLSQL ,can anyone suggest me for any institutes in bangalore or how to prepare for interviews

2014

when we are importing items in inventory, showing errors, Oracle support suggested us for running scripts & also suggested if we run scripts, iprocurement applicaation if is there it will show shared and if we go in future for iprocurement, it wont work. So kinldy suggest any functional solution.

1994

any body know about orawaves do they really provide placements in their unique placement program

TCS,

1 4129

Table - Products has number of products as below Productid ProductName 1 iPhone 2 iPad 3 BlackBerry Table - SalesPersonProduct has the below records Salespersonid productid S1 1 S1 2 S1 3 S2 1 S3 2 Write a SQL query that returns the total number of sold products

2831

2 6632

what is tkprof tool and how it is used???

Genpact,

2829

how do see how much space is used and free in a tablespace

Genpact,

2 7773

1. how do you delete duplicate rows in a table? 2. can you disable and enable primary key? 3. how do you move tables from one tablespace to another tablespace?????

Genpact,

2 6719

primary key is foreign key for the same table?

Oracle,

2 7197

Hi All, I am new to both this blog and technology. I was able to see a response for one of the questions on triggers as below. I would like to know why are we using " if rtrim(to_char(sysdate,'day'))=rtrim('sunday') then" instead, can't we use " if sysdate = 'sunday' then". I can understand the use of "rtrim", but dont know y v r using to_char. I have seen this in many cases but did not get a convincible explaination. Please help me with this and do excuse if this question sounds silly. Thanks in advance...... create or replace trigger trg_sun before insert on

begin if rtrim(to_char(sysdate,'day'))=rtrim('sunday') then raise_application_error(-20345,'no transaction in sunday'); end if; end trg_sun;

2 4309

I want to reuse a piece of code inside a stored procedure. This piece of code need to be invoked multiple times inside the procedure based on some different conditions. How to achieve this?

1 3944

1) What is dense ranking? 2) Difference between Substring and Instring? 3) Case and Decode? 4) Pseudo column? 5) View vs Materialized views? 6) SQl performance tuning?

Accenture,

2 6999

how to check the 3rd max salary from an employee table? One of the queries used is as follows: select sal from emp a where 3=(select count(distinct(sal)) from emp b where a.sal<=b.sal). Here in the sub query "select count(distinct(sal)) from emp b where a.sal<=b.sal" or "select count(distinct(sal)) from emp b where a.sal=b.sal" should reveal the same number of rows is in't it? Can any one here please explain me how is this query working perfectly. However, there is another query to get the 3rd highest of salaries of employees that logic I can understand. Pls find the query below. "select min(salary) from emp where salary in(select distinct top 3 salary from emp order by salary desc)" Please explain me how "select sal from emp a where 3=(select count(distinct(sal)) from emp b where a.sal<=b.sal)" works source:http://www.allinterview.com/showanswers/33264.html. Thanks in advance Regards, Karthik.

4 8459

Display the total debit counts, total credit counts, sum of total debits, sum of total credits from an employee's transaction table (a single table) containing the following columns. Transaction_number Transaction_amount Transaction_date Transaction_type --> tells if the amount is a credit or a debit. As the query alone is important, the table is left with specifying just the field's name. Pls help me with this query.

iNautix, Oracle,

3 17894

Un-Answered Questions { Databases }

What are the built in functions of sql?

1030

What is basic structure of pl sql?

1068

What is the use of sp_helprotect in sybase?

968

How to resolve the ORA-39133 error in Oracle?

1113

Can cursors be part of a trigger body?

1641

What are key constraints?

974

What is bcnf in the dbms?

938

What are the roles and responsibilities of oracle dba?

638

What is data block and how to define data block size?

1026

What is the difference between the repeatable read and serializable isolation levels? : Transact sql

1098

Does inner join return duplicate rows?

976

What do you mean by oracle dba and what is its role?

586

describe middleware applications that ease the connection of databases to web?

932

How do you check database space?

1010

Explain go command in sql server?

1033

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