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

What is difference between process and thread? Explain lazy writer funcationality.

Microsoft,

2 8287

What is live lock and deadlock? what is Lock escalation?

Microsoft,

2 9440

How to fetch/retrieve the data from hieranchical database and put it into the relational database? for e.g I want to extract the data from IMS DB2 database which is a hierarchical db and load that data into the relational database which is a SQL server.Are there any tools available for directing extracting data from hierarchical db and loading into the relational database (SQL server)?

1 1985

when a grant option is encountered for a table EMP to a peer sitting beside you who has already having the table of that name (EMP), then what is the result?

2 4418

select top 3 sal from each dept?

IBM, TCS,

17 28083

I have table that has student names in it.If I query on the names my result set should return as 'VALUE NOT ENTERED' for null entries.

1 4379

What is the best way to move n number of DTS package from one SQLServer to another SQLServer?

RBS,

1 4507

mysql> select * from store; +------+-------+-------+ | id | month | sales | +------+-------+-------+ | 1 | 1 | 100 | | 1 | 2 | 100 | | 1 | 3 | 200 | | 1 | 4 | 300 | | 1 | 5 | NULL | | 1 | 6 | 200 | | 1 | 7 | 800 | | 1 | 8 | 100 | | 1 | 9 | 240 | | 1 | 10 | 140 | | 1 | 11 | 400 | | 1 | 12 | 300 | | 2 | 1 | 300 | | 2 | 2 | 300 | | 2 | 3 | 300 | | 2 | 4 | 200 | | 2 | 5 | 200 | | 2 | 6 | 200 | | 2 | 7 | 100 | | 2 | 8 | 100 | | 2 | 9 | 300 | | 2 | 10 | 100 | | 2 | 11 | 150 | | 2 | 12 | 150 | +------+-------+-------+ this is my table. i need to display output like this. +------+----------+----------+----------+----------+ | id | quarter1 | quarter2 | quarter3 | quarter4 | +------+----------+----------+----------+----------+ | 1 | 400 | 500 | 1140 | 840 | | 2 | 900 | 600 | 500 | 400 | +------+----------+----------+----------+----------+ what single query i have to write for this. i tried this query and it displays like the below mysql> select id,sum(sales) as quarter1,(select sum(sales) from store where mont h>3 and month<7 ) as quarter2,(select sum(sales) from store where month>6 and mo nth<10)as quarter3 from store where month>0 and month<4 group by id; +------+----------+----------+----------+ | id | quarter1 | quarter2 | quarter3 | +------+----------+----------+----------+ | 1 | 400 | 1100 | 1640 | | 2 | 900 | 1100 | 1640 | +------+----------+----------+----------+ 2 rows in set (0.00 sec) tel me how to rectify it.

2 4649

Single File Database: Develop a student record management program, which uses single file as its database. It is not supposed to create additional files at any part of the project and should never rewrite total content. It must be capable of storing 100000's of records. It should support variable length records to be added, deleted, modified, listed.

1 2279

How to update rows in table, suppose i have lacks of rows in table how to update total table with update statement. Can u please any one answer this question with update statement.

2 5113

What is Primary key and foreign key? Give an example

TCS,

4 9954

How to connect PK and FK?

2 6181

Can you export a table along with partition?

1 3731

what is datapump? Difference between exp and expdp?

Capital IQ, TCS, WNS,

2 21871

I have query like this. select dept_id, max_mark from stude_dept where min_mark= (select min(mini_mark) from stud_dept); How can i optimize this query. Can anyone help me with it

2 5006

Un-Answered Questions { Databases }

what is sql server agent? : Sql dba

1162

What are the properties of the transaction?

1059

What are different types of constraints?

981

explain different types of backups avaialabe in sql server? Given a particular scenario, how would you go about choosing a backup plan? : Sql server database administration

1118

how to escape special characters in sql statements? : Sql dba

1097

What is the best sql course?

1031

Suppose database is running slow, what will you do?

2580

What is temporary table in sql server? Why we use temp table?

1000

Is microsoft getting rid of access?

877

8. Sort, Lookup What kind of technique (partition) is used? 9. How can you handle exceptions in job sequencer? 10. How do you apply custom conditions an exceptions (How do you trigger exceptions in job sequence?) 11. I have a job with 3 possibilities? Finish with ok…..Abort…….Warning} How do you handle these in Job sequencer 12. How do you connect both OK and Warning can we? 13. How to find which process is running currently? 14. How do you find the disk usage in UNIX? 15. How do you combine 2 sequential files having same metadata of same file names? 16. How do you implement SCD in Ds? 17. Explain the situation where you have applied? 18. How do you apply new changes to? 19. Difference between change capture and Change apply? 20. Explain Compare Stage? 21. What is Surrogate key? 22. How to solve the problem of null values?

1899

how many tables will create when we create table, what are they? : Sql dba

1129

What are wait types?

1219

1. Tell me about your self? 2. Latest Project Introduction? 3. Difference between server jobs and parallel jobs? 4. Seq-Seq Explain its behavior and execution mode and which parallelism technique is used? 5. What is padding characters? 6. Seq-Seq, Seq-Copy-Seq which one is the best and efficient? 7. How many reject links do we have to a transformer? 8. How many reject links to join stage? 9. Difference between join and lookup? 10. How to design PX routine? 11. How can we call job in another job? 12. Difference between batch and sequencer? 13. Which Database is used? 14. What is change capture? Give briefing of that? 15. What is change Code? Explain? 16. How you call UNIX in Ds? 17. How do you call JCL in UNIX? 18. How do you pass the job status of one job to another job? Have designed any job sequencer? 19. How do you find a file in existed directory? 20. How can you call parallel jobs in transformer? 21. Execution of jobs in command line? 22. Tuning of sql queries? 23. What is orchestrating metadata? 24. What are junk dimension? 25. What are the third party tools you are used? 26. What are the system variables you have used? IBM 1. What is virtual dataset? 2. How do you handle reject link to a peek stage? 3. What is transaction table? 4. Which one is the efficient from the following? a. ODBC enterprise b. Oracle enterprise 5. How can you extract data from excel sheet? Do you know how to parameterize, this option? 6. Six pages of complex query I have, how do you simplify this query? 7. Difference between dataset and lookup file set?

1959

what is schema? : Sql dba

1124

How to Change a users password from unix shell.

1193

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