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

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DB Architecture (141)
DB Administration (291)

DB Development (113)
SQL PLSQL (3330)
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Database Management (1411)
Databases AllOther (288)

Databases Interview Questions

Questions Answers Views Company eMail

What is the difference between truncate and delete? How would a full table scan behave after?

511

What is difference between co-related sub query and nested sub query?

528

What is oracle full backup?

518

What is pga_aggregate_target?

524

A dba had to remove some archivelogs to free up space in filesystem. Nowwhen the rman job starts to backup archivelogs, it complains about missing archivelogs thatwere deleted by dba. To resolve the issue and continue backing up remainder of archivelogs,which rman command can be used so it wo not complain about missing archivelogs.

562

What are the tradeoffs between many vs few indexes? When would you want to have many, and when would it be better to have fewer?

581

If you had a tablespace, test_tablespace, which consists of three files:test01.dbf, test02.dbf, and test03.dbf, and someone accidentally used the unix command"rm" to delete the file test02.dbf, what else would you need in order to recover all the data thatwas present in test_tablespace at the time that test02.dbf was deleted?

532

Tell me about standby database? What should we watch out for?

504

What is the difference between a materialized view (snapshot) fast refresh versus complete refresh? When is one better, and when the other?

541

Explain the wait events in statspack report 'db scattered read', 'db sequential real', 'enqueue'?

614

What are the steps involved in instance recovery in oracle?

502

What is oracle log switch?

559

What does the no logging option do? Why would we use it? Why would we be careful of using it?

506

How do I call oracle stored procedures that take no parameters?

1026

How do I learn what codesets are available in oracle?

999

Un-Answered Questions { Databases }

What is linq to sql?

1061

What is the difference between 3 tier and 3 layer architecture?

761

What are the features of dbms?

883

What is a sequence table in postgresql?

754

What is row_number () and partition by in sql server?

1007

Where cross join is used?

905

What is record in pl sql?

1011

What is the main purpose of a database?

874

How do I check mysql version?

959

what is normalisation?what are its uses?

2213

Write a query to fetch common records between two tables using mysql?

960

Which data types generate inaccurate results if used with an = or <> comparison in a where clause of a sql statement?

996

What are the advantages of using third-party tools?

921

Is sybase owned by sap?

848

How to define the name and server for a new dsn?

1011

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