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 31418

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

2062

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.

2043

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

TCS,

1 4193

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

2880

2 6705

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

Genpact,

2882

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

Genpact,

2 7896

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 6819

primary key is foreign key for the same table?

Oracle,

2 7317

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 4410

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 4038

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 7115

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 8618

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 18047

Un-Answered Questions { Databases }

Are stored procedures compiled?

980

What do you mean by foreign key and primary key?

1088

Can composite key be null?

894

What is the usage of analyze command in oracle?

1141

Is it possible to sort a column using a column alias?

1100

How we can see all indexes defined for a table in mysql?

998

What is cached report?

150

Is it good to save image in database?

1075

How to add new field to existing document in mongodb using java?

What is longblob?

1040

How many segment are present in Oracle Manufacturing

2371

How to drop an existing schema in ms sql server?

1144

How to start an oracle instance?

1072

Sql technical questions

1334

Explain about recursive stored procedures?

848

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