Oracle PL/SQL Fundamentals

Wednesday, December 31, 2008

Which one of the following built-in packages do you use to work around the previous 1,000,000 hard limit on the buffer size of DBMS_OUTPUT for any session when directly writing output from PL/SQL?
Choice 1 : DBMS_PIPE
Choice 2 : DBMS_IO
Choice 3 : UTL_FILE
Choice 4 : UTL_PIPE
Choice 5 : DBMS_FILE

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Scenario
The database has reported the error:
ORA-04091: table is mutating, trigger/function may not see it.
What is one possible explanation for the error displayed in the scenario above?
Choice 1 : A statement trigger your statement fired has executed an improperly formed Select result, resulting in a large Cartesian product.
Choice 2 : You have attempted to change a table currently being updated by a row trigger another user has fired.
Choice 3 : Another user has changed a table referenced by a row trigger that your statement fired.
Choice 4 : A statement trigger that your statement fired has attempted to select from a global temporary table.
Choice 5 : A row trigger that your statement fired has attempted to access its triggering table.

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Scenario
You have data containing a numeric postal code in the form nnnnn-zzzz, where the -zzzz is an optional item that you want to capture if available. You want to isolate the postal code from the line of text in which it appears.

The data is stored in address in the form:

City, State Postal Code

Given the scenario described above, which one of the following regular expressions isolates the postal code?
Choice 1 : SELECT REGEXP_SUBSTR(address, '[[:digit:]]{5}') post_code FROM dual;
Choice 2 : REGEXP_SUBSTR(address, '[[:digit:]]{5}(-[[:digit:]]{4})*$')
Choice 3 : SELECT REGEXP_INSTR(address, '[[:digit:]]{5}', 1, 1, 0, 'i') FROM datatable;
Choice 4 : SELECT REGEXP_SUBSTR(address, '[[:digit:]]{5}', 1, 1, 0, 'i') FROM datatable;
Choice 5 : REGEXP_LIKE(address, '[[:digit:]]{5}.*[[:space:]]')

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Which one of the following is a fundamental difference between WHILE Loops and numeric FOR Loops?
Choice 1 : When numbers are used in a WHILE Loop, they are actually character data; numeric FOR Loops use binary_integer values.
Choice 2 : WHILE Loops cannot be based on numeric conditions; numeric FOR Loops are always based on numeric conditions.
Choice 3 : WHILE Loops terminate explicitly; the termination point of numeric FOR Loops is stated implicitly.
Choice 4 : WHILE Loops depend on the state of a variable and terminate when the state changes; FOR Loops do not.
Choice 5 : The number of iterations a WHILE Loop makes is unknown or not specified; numeric FOR Loops are designed to loop a specific number of times.

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Scenario
You are creating a routine to update the database that uses a transaction. You need to create a transaction in which queries within that transaction see only changes that were committed before the transaction began.

Given the scenario described above, which command do you use to limit queries to the data you need?
Choice 1 : SET TRANSACTION ISOLATION LEVEL READ ONLY
Choice 2 : ROLLBACK
Choice 3 : SET QUERY SCOPE COMMITTED
Choice 4 : ROLLBACK TO COMMITTED
Choice 5 : LIMIT QUERY TO COMMITTED

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For which one of the following do you use the NULL statement?

Choice 1 : To perform no operation
Choice 2 : To execute in real-time mode
Choice 3 : To return an undefined value
Choice 4 : To pause execution for 50 milliseconds and, often, to time sensitive areas of code
Choice 5 : To call an exception handler

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Scenario
You have two strings that you need to join together to make one string. One string is in variable a and the other is in variable b. You want b to precede a.
Given the scenario described above, which command do you use to join together two separate strings?
Choice 1 : RIGHT JOIN (a,b)
Choice 2 : LPAD (b,a)
Choice 3 : LEFT JOIN (a,b)
Choice 4 : CONCAT(b, a)
Choice 5 : SUBSTR (b,a)

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Oracle PL/SQL Fundamentals

With regard to performance, why do you combine SQL statements into PL/SQL blocks?
Choice 1 : More debugging information is available for SQL statements within PL/SQL.
Choice 2 : The query optimizer is run during compile time only.
Choice 3 : Authentication time is decreased.
Choice 4 : Network traffic is decreased.
Choice 5 : Storage requirements are decreased.

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Scenario
You want to use the DBMS_LDAP functions and procedures, but when you try to use them, you receive an error that indicates that DBMS_LDAP cannot be found.
Given the scenario described above, how do you enable DBMS_LDAP?
Choice 1 : Turn off basic authentication.
Choice 2 : Set the LDAP server to authenticate using version 3 of the protocol.
Choice 3 : Add the shared object files for the LDAP implementation you are using.
Choice 4 : Load $ORACLE_HOME/rdbms/admin/catldap.sql.
Choice 5 : Import the LDAP binary drivers.

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Which one of the following is a PL/SQL subprogram?
Choice 1 : UPDATE
Choice 2 : PROCEDURE
Choice 3 : ANONYMOUS BLOCK
Choice 4 : DBMS_SESSION
Choice 5 : PACKAGE
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Scenario
You are using a cursor named employee_cur in a program. Your program occasionally displays ORA-06511: PL/SQL: cursor already open; you would like to eliminate that error.
Given the scenario described above, how do you eliminate the error in your program?
Choice 1 : Clear the cursor cache by issuing cursorsync prior to opening employee_cur.
Choice 2 : Delete all records from the v$open_cursor view.
Choice 3 : Open the cursor only if employee_cur%ISOPEN is false.
Choice 4 : Synchronize v$librarycache.
Choice 5 : Delete records with a Type of Cursor from the v$bh view.

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Which one of the following implicit datatype conversions is supported in Oracle?
Choice 1 : NUMBER to ROWID
Choice 2 : DATE to VARCHAR2
Choice 3 : DATE to BLOB
Choice 4 : NUMBER to DATE
Choice 5 : ROWID to DATE

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Scenario
You have a project that requires for SQL code to adhere to the ISO SQL standard. You need to perform explicit conversions between data types.
Given the scenario described above, which command do you use?
Choice 1 : TO_NUMBER
Choice 2 : CONVERT
Choice 3 : TO_CHAR
Choice 4 : TYPE
Choice 5 : CAST

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Scenario
Your company is implementing several security imperatives. To comply with one of the imperatives; you need to limit the file system directories that are accessible via UTL_FILE.
Given the scenario described above, how do you allow only specific directories to be accessible?
Choice 1 : Define the value PL_ALLOWED_DIR with the allowed directories in V$SYSTEM
Choice 2 : Set the file system to be read-only.
Choice 3 : Set the file system with the NOSUID attribute.
Choice 4 : Set UTL_FILE_DIR='/allowed/directory' in INIT.ORA
Choice 5 : Use the command INSERT INTO V$FILES (UTIL_FILE) VALUES ('/allowed/directory');.

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Scenario
You have a large database configured. You want to allow a portion of a transaction to be rolled back after a certain point in processing.
Given the scenario described above, which one of the following commands do you use to mark the spot for rollback?
Choice 1 : BOOKMARK
Choice 2 : SAVEPOINT
Choice 3 : COMMIT TO
Choice 4 : SET TRANSACTION
Choice 5 : ROLLBACK TO

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Sample Code
TYPE relatives IS TABLE OF relatives%ROWTYPE
INDEX BY BINARY_INTEGER;

The sample code above is an example of which one of the following?

Choice 1 : A PL/SQL record
Choice 2 : A PL/SQL table type
Choice 3 : A PL/SQL table
Choice 4 : A PL/SQL table index
Choice 5 : A multi-row table variable

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Oracle PL/SQL Fundamentals

Scenario : You are in the process of issuing several UPDATE statements within a single transaction. During this transaction, an update fails and you issue a rollback.
Given the scenario described above, what happens to the database?
Choice 1 : A transaction is valid ONLY for INSERT statements; therefore, all UPDATE statements will be written to the database.
Choice 2 : The database retries the failed UPDATE statement one more time and undoes its action if it fails again.
Choice 3 : The successful UPDATE statements are permanently written to the database. The last UPDATE did not get committed and was rolled back.
Choice 4 : All UPDATE statements within the transaction are rolled back and the database is consistent with its state before the transaction.
Choice 5 : All data is reverted to the state the database was in when it was first started.
===================================================================

Scenario : You are using an IF-THEN-ELSIF-ELSE-END IF statement, and all the conditions specified evaluate to NULL.
Given the scenario described above, which one of the following statements is executed?
Choice 1 : One of the ELSIF parts
Choice 2 : The NULL value handler
Choice 3 : The ELSE part
Choice 4 : The divide by zero exception handler
Choice 5 : The IF part
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Scenario : There is a package named UTILPKG, which contains 84 procedures and 16 functions.

Referring to the scenario above, when you call a function UTILPKG.file_rename, which one of the following fully describes what is loaded into memory?

Choice 1 : Both the function specification and definition for UTILPKG.file_rename and dependencies in UTILPKG are loaded.
Choice 2 : Both the entire package specification and body for UTILPKG are loaded.
Choice 3 : Only the function definition for UTILPKG.file_rename and its dependencies, if UTILPKG.file_rename has cursor references in the specification, is loaded.
Choice 4 : Only the function definition for UTILPKG.file_rename
Choice 5 : Only the function specification for UTILPKG.file_rename
===========================================================================================
Scenario : You have the following string:

This is a test. This is only a test.
You want to replace every occurrence of the word test with the word trial.

Given the scenario described above, which one of the following commands do you use to accomplish this?
Choice 1 : 'This is a test. This is only a test.' =~ s/test/trial/g
Choice 2 : 'This is a test. This is only a test.' =~ s/test\./trial\./
Choice 3 : SUBSTR('This is a test. This is only a test.','test','trial')
Choice 4 : REPLACE('This is a test. This is only a test.', 'test','trial')
Choice 5 : UPDATE('This is a test. This is only a test.' set 'test','trial')
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Which one of the following is a data definition language (DDL) command?
Choice 1 : INSERT
Choice 2 : TRUNCATE
Choice 3 : DELETE
Choice 4 : SELECT
Choice 5 : UPDATE
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Oracle stores P-code in the database for which one of the following structures?
Choice 1 : Indexes
Choice 2 : Named PL/SQL blocks
Choice 3 : ODBC clients
Choice 4 : Object relational models
Choice 5 : Anonymous PL/SQL blocks
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Oracle PL/SQL Fundamentals

Thursday, December 25, 2008

Scenario: You have a database that uses a computationally intensive calculation that is accessed often in a SELECT query. You want to improve the execution speed of this calculation.

Given the scenario described above, which one of the following do you use to accomplish this?
Choice 1 : Global and local index
Choice 2 : B-tree cluster index
Choice 3 : Function-based index
Choice 4 : Real Application Cluster with load balancing enabled
Choice 5 : The parallel computing package

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When tracing is enabled, which one of the following scripts do you run in order to create the tables that collect trace information generated by DBMS_TRACE?

Choice 1 : TRACETAB.sql
Choice 2 : UTLXTRC.sql
Choice 3 : TRCTABLE.sql
Choice 4 : DBMSTRC.sql
Choice 5 : PLSQLTRC.sql

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Scenario : You need to create 50 tables. The names are based on parameters stored in an existing table. You have created a PL/SQL program that retrieves the data from the table and loops through each item. The program outputs the correct data when you use dbms_output.put_line('CREATE TABLE ' || X || '(a number)'), but when you try to execute CREATE TABLE X (A number) it does not function.

Given the scenario described above, which one of the following do you do in order for the CREATE TABLE statement to function properly?
Choice 1 : Precede the statement with EXECUTE IMMEDIATE.
Choice 2 : Pipe the output to the DBMS.SQL function.
Choice 3 : Update the program state to DDL mode before executing the statement.
Choice 4 : Clear the statement cache prior to executing the statement.
Choice 5 : Close any existing open cursors before running the statement.
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When you store a PL/SQL table (Table type) in the database, how many columns does the table have?
Choice 1 : 1
Choice 2 : 2
Choice 3 : 3
Choice 4 : As many as are necessary in the program
Choice 5 : One plus the number of columns in the nested table
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Scenario : You have created a new database. You want to use DBMS_PROFILER to measure execution time of a pl/sql program unit. When you try to use DBMS_PROFILER, you find that it is not available.
Given the scenario described above, how do you make DBMS_PROFILER available for use?
Choice 1 : Create the stats collection table in your database.
Choice 2 : Execute dbms_profiler.flush_data.
Choice 3 : Run profload.sql as sys and proftab.sql as the profile user.
Choice 4 : Increase the system global area heap size to at least two gigabytes.
Choice 5 : Set serverprofiler on enabled.
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Which one of the following is a common reason for slow PL/SQL program execution?
Choice 1 : Setting garbage collection intervals
Choice 2 : Forgetting to SET SERVEROUTPUT ON
Choice 3 : Disabling the Oracle Trace facility
Choice 4 : Writing SQL statements that are not optimized
Choice 5 : Neglecting to specify as many columns as possible to be NOT NULL during table creation
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For which one of the following purposes do you use regular expressions?
Choice 1 : Matching text patterns
Choice 2 : Balancing binary trees
Choice 3 : Tracking changes over time
Choice 4 : Improving readability of code
Choice 5 : Describing the purpose of a function or statement
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Why do you use cursor attributes?
Choice 1 : To open and close cursors
Choice 2 : To populate cursors
Choice 3 : To record cursor execution time
Choice 4 : To control cursors
Choice 5 : To get information about cursors
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Scenario : You have the following line of code in a program:

statement := "SELECT * FROM users WHERE name = '" + Name + "';"

The line is called from an application running on a public facing Web server. Given the scenario described above, what is the security issue with this code?

Choice 1 : SQL injection
Choice 2 : Fragment attack
Choice 3 : Buffer overflow
Choice 4 : Heap exhaustion
Choice 5 : Spoofing attack
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ASP.net Interview Questions - 6

Friday, September 19, 2008

What is CLS (Common Language Specificaiton)?
It provides the set of specificaiton which has to be adhered by any new language writer / Compiler writer for .NET Framework. This ensures Interoperability. For example: Within a ASP.NET application written in C#.NET language, we can refer to any DLL written in any other language supported by .NET Framework. As of now .NET Supports around 32 languages.


What is CTS (Common Type System)?
It defines about how Objects should be declard, defined and used within .NET. CLS is the subset of CTS.

What is Boxing and UnBoxing?
Boxing is implicit conversion of ValueTypes to Reference Types (Object) .
UnBoxing is explicit conversion of Reference Types (Object) to its equivalent ValueTypes. It requires type-casting.

What is the difference between Value Types and Reference Types?
Value Types uses Stack to store the data where as the later uses the Heap to store the data.

What are the different types of assemblies available and their purpose?
Private, Public/shared and Satellite Assemblies.

Private Assemblies : Assembly used within an application is known as private assemblies

Public/shared Assemblies : Assembly which can be shared across application is known as shared assemblies. Strong Name has to be created to create a shared assembly. This can be done using SN.EXE. The same has to be registered using GACUtil.exe (Global Assembly Cache).

Satellite Assemblies : These assemblies contain resource files pertaining to a locale (Culture+Language). These assemblies are used in deploying an Gloabl applicaiton for different languages.

Is String is Value Type or Reference Type in C#?
String is an object (Reference Type).

Which controls do not have events?
Ans:Timer control.

What is the maximum size of the textbox?
Ans:65536.

Which property of the textbox cannot be changed at runtime?
Ans:Locked Porperty.

Which control cannot be placed in MDI?
Ans:The controls that do not have events.

Difference between a sub and a function.
Ands -A Sub Procedure is a method will not return a value
-A sub procedure will be defined with a “Sub” keyword
Sub ShowName(ByVal myName As String)
Console.WriteLine(”My name is: ” & myName)
End Sub

-A function is a method that will return value(s).
-A function will be defined with a “Function” keyword
Function FindSum(ByVal num1 As Integer, ByVal num2 As Integer) As Integer
Dim sum As Integer = num1 + num2
Return sum
End Function

Explain manifest & metadata.
Ands: Manifest is metadata about assemblies. Metadata is machine-readable information about a resource, or “”data about data.” In .NET, metadata includes type definitions, version information, external assembly references, and other standardized information.

Difference between imperative and interrogative code
Ans. There are imperative and interrogative functions. Imperative functions are the one which return a value while the interrogative functions do not return a value.

What are the two kinds of properties
Ans. Two types of properties in .Net: Get & Set
Two kind of properties are scalar properties and indexed properties

Explain constructor
Ans. Constructor is a method in the class which has the same name as the class (in VB.Net its New()). It initialises the member attributes whenever an instance of the class is created.

Describe ways of cleaning up objects
Ans. The run time will maintain a service called as garbage collector. This service will take care of deallocating memory corresponding to objects. It works as a thread with least priority.when application demands for memory the runtime will take care of setting the high priority for the garbage collector,so that it will be called for execution and memory will be released.the programmer can make a call to garbage collector by using GC class in system name space.

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ASP.net Interview Questions - 5

Question:-What is cross page posting in ASP.NET2.0 ?
Answer: When we have to post data from one page to another in application we used server.transfer method but in this the URL remains the same but in cross page posting there is little difference - normal post back is done but in target page we can access values of server control in the source page.This is quite simple we have to only set the PostBackUrl property of Button,LinkButton or imagebutton which specifies the target page.In target page we can access the PreviousPage property.And we have to use the @PreviousPageType directive.We can access control of PreviousPage by using the findcontrol method.When we set the PostBackURL property ASP.NET framework bind the HTML and Javascript function automatically.

Question: What you think about the WebPortal ?
Answer: Web portal is nothing but a page that allows a user to customize his/her homepage. We can use Widgets to create that portal. We have to only drag and drop widgets on the page. The user can set his Widgets on any where on the page. Widgets are nothing but a page area that helps particular function to response. Widgets example are address books, contact lists, RSS feeds, clocks, calendars, play lists, stock tickers, weather reports, traffic reports, dictionaries, games etc.

Question: How to start Outlook,NotePad file in ASP.NET with code ?
Answer: To open outlook or notepad file in
ASP.NET or VB.NET
Process.Start("Notepad.exe")
Process.Start("msimn.exe");
C#.NET
System.Diagnostics.Process.Start("msimn.exe");
System.Diagnostics.Process.Start("Notepad.exe");

Question: What is the purpose of IIS ?
Answer: IIS(Internet Information Services) a powerful Web server that helps us creating highly reliable, scalable and manageable infrastructure for Web application which runs on Windows Server 2003. IIS helps development center and increase Web site and application availability while lowering system administration costs. It also runs on Windows NT/2000 platforms and also for above versions. With IIS, Microsoft includes a set of programs for building and administering Web sites, a search engine, and support for writing Web-based applications that access database. IIS is also called http server since it process the http request and gets http response.

Question: What is main difference between GridLayout and FormLayout ?
Answer: GridLayout helps in providing absolute positioning of every control placed on the page.It is easier to devlop page with absolute positioning because control can be placed any where according to our requirement.But FormLayout is little different and only experience Web Devloper used this one reason is it is helpful for wider range browser.If there is absolute positioning we can notice that there are number of DIV tags.But in FormLayout whole work are done through the tables.

Question: How Visual SourceSafe helps Us ?
Answer: One of the powerful tool provided by Microsoft to keep up-to-date of files system its keeps records of file history once we add files to source safe it can be add to database and the changes added by different user to this files are maintained in database from that we can get the older version of files to.This also helps in sharing,merging of files.

Question: Com Marshler function in .NET ?
Answer: Com Marshler is useful component of CLR.Main work of marshal data between Managed and Unmanaged environment .It helps in representation of data accross different execution enviroment.Its also convert data format between manage and unmanaged code.By the helps of Com Marshlar CLR allows manage code to interoperate with unmanaged code.

What is ViewState?
ViewState allows the state of objects (serializable) to be stored in a hidden field on the page. ViewState is transported to the client and back to the server, and is not stored on the server or any other external source. ViewState is used the retain the state of server-side objects between postabacks.

What is the lifespan for items stored in ViewState?

Item stored in ViewState exist for the life of the current page. This includes postbacks (to the same page).

What does the "EnableViewState" property do? Why would I want it on or off?

It allows the page to save the users input on a form across postbacks. It saves the server-side values for a given control into ViewState, which is stored as a hidden value on the page before sending the page to the clients browser. When the page is posted back to the server the server control is recreated with the state stored in viewstate.

What are the different types of Session state management options available with ASP.NET?

ASP.NET provides In-Process and Out-of-Process state management. In-Process stores the session in memory on the web server. This requires the a "sticky-server" (or no load-balancing) so that the user is always reconnected to the same web server. Out-of-Process Session state management stores data in an external data source. The external data source may be either a SQL Server or a State Server service. Out-of-Process state management requires that all objects stored in session are serializable.

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Business Objects - 3

Tuesday, July 22, 2008

21. what is the source for metrics?
Measure objects.

22. Why do we need metrics and sets?
Metrics are used for analysis and Sets are used for grouping.

23. Is there any bug in 6.x?
In earlier version of 6.0 they had, but 6.5 is the best version with out any bugs.

24. What are the general issues in migration process?
Alignment, performance.

25. What is the use of BO SDK?
Bo SDK's main use is to suppress “no data to fetch” using Macros.

26. How can we improve performance?
By making use of Aggregate tables.

27. Analysis in BO?
Slice-Dice and Drill analysis.

28. How can you check the integrity?
By making use of Check integrity button.

29. What are Universe parameters?
Name of the universe, description and RDBMS connection, size and rights.

30. Types of Universes?
Simple and Complex.

31. What is the use of BCA?
BCA is used to refresh and schedule and export and save as .html, .rtf, .xls , .pdf.

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Business Objects - 2

11. What do you mean by Object qualification?
Object qualification represents what kind of object is that, usually we have three types of object qualifiers they are measure, dimension, detailed.

12. What is the size of data base?
In general it will be anything between 4-8 Terabytes.

13. What is a loop? How can we overcome?
Loop is nothing but a closed circular flow; it can be overcome by making use of Alias and Context.

14. What is a join? Explain different types of joins?
Join is used to link to tables depending upon the data requested by the user, Usually we have Inner Join, Outer Join, Left Join, Right Join, Full Outer join.

15. What are Linked Universes?
If the data provided is from two different data providers then we can link those two universes, such type of universe is called Linked Universe.

16. What are Alerter, Filters, Breaks and Conditions?
Alters are nothing but they are used to draw attention to a block of data by highlighting.
Breaks are nothing but grouping the data without any change in the format.
Condition is used to retrieve data which meets certain criteria.
Filters are used to get necessary data.

17. What is the difference between master-detail and Breaks?
In break common fields are deleted (here in this case the table format is not changed) whereas in master-detail , we declare certain entity as a master to get the detailed information or report in this case the table format is changed.

18. What is metrics?
Metrics are a system of parameters or ways of quantitative and periodic assessment of a process that is to be measured; these are used to track trends, productivity.

19. What is a Set?
Its nothing but grouping of users.

20. What is the use of AFD? Where it can be stored?
AFD is used to create dashboards. It can be stored in repository, corporate or personal.

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Business Objects - 1

1. Explain detail objects?
Detail objects are attached to dimensions, one cannot drill on details nor link on details when linking multiple data providers. While Customer ID would be a dimension, customer name, address, phone and so on should be details.

2. What is BOMain.Key?
BoMain.Key file contains the information about the repository site i.e it contains the address of the repository security domain.

3. What is Business objects Repository?
It is nothing but metadata.

4. What is domain? How many are there in a basic setup? What are they?
Domain is nothing but logical grouping of system tables. There are three domains usually in a basic setup. They are Secure, Universe, Document. Business objects are sometimes called domain objects (where the word domain means the business), and a domain model represents the set of domain objects and the relationships between them.

5. When is the Repository created?
In 5i/6i versions after installing the software, whereas in Xi version a repository is created at the time of installation.

6. Can we have multiple domains?
Yes. (Security domain can not be multiple).

7. How do you restrict access to rows of a database?
In XI version it can be done by using row-level security in designer module whereas in 5i/6i it is done by supervisor.

8. What is a category?
It is nothing but grouping of certain entities.

9. What is a Universe?
It is a semantic layer between Database and the designer used to create objects and classes. (It maps to data in Database).

10. What is an Object?
It is an instance of class, its nothing but an entity.

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DataWare Housing Glossary of Terms - 'T'

Sunday, July 20, 2008

Table a relation that consists of a set of columns with a heading and a set of rows.
Time Variant Data data whose accuracy is relevant to some one moment in time.
Top down methodology Involves in building a datawarehouse first and then building datamarts..
Transaction Processing the activity of executing many short, fast running programs, providing the end user with consistent two or three second response time.
Transition Data data possessing both primitive and derived characteristics; usually very sensitive to the running of the business.

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DataWare Housing Glossary of Terms - 'S'

Schema The logical organization of data in a database.
Scope of Integration the formal definition of the boundaries of the system being modelled.
Sequential File a file in which records are ordered according to the values of one or more key fields.
Serial File a sequential file in which records are physically adjacent, in sequential order.
Slowly Changing Dimensions The approaches involving maintaining a list or history by adding related rows or new columns, or simply ignoring the problem by retaining the only the current data.Type I, Type II, Type III
Snowflake Schema A snowflake schema is a set of tables comprised of a single, central fact table surrounded by normalized dimension hierarchies. Each dimension level is represented in a table. Snowflake schema implement dimensional data structures with fully normalized dimensions. Star schema are an alternative to snowflake schema.
Star Schema A star schema is a set of tables comprised of a single, central fact table surrounded by de-normalized dimensions. Each dimension is represented in a single table. Star schema implement dimensional data structures with de-normalized dimensions. Snowflake schema are an alternative to star schema.
Surrogate Key It has system-generated artificial primary key values, which allows to maintain historical records in the Data Warehouse more effectively.

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DataWare Housing Glossary of Terms - 'Q' & 'R'

Query Language a language that enables an end user to interact directly with a DBMS to retrieve and possibly modify data managed under the DBMS.

Record an aggregation of values of data organized by their relation to a common key.
Recovery the restoration of the database to an original position or condition, often after major damage to the physical medium.
Redundancy the practice of storing more than one occurrence of data.
Referential Integrity the facility of a DBMS to ensure the validity of a predefined relationship.
Refresh Refreshing a warehouse consists in propagating updates on source data to correspondingly update the base data and derived data stored in the warehouse. Two sets of issues to consider; when to refresh and how to refresh. Refresh policy is set by warehouse administrator, depends on user needs and traffic and may be different for different sources.
Replication The physical copying of data from one database to another.
Reporting The process of translating data to presentation formats via a pre-defined or ad-hoc queries.
ROLAP Relational OLAP. Data warehouses that are implemented on standard or extended relational DBMSs,called Relational OLAP(ROLAP)servers.These servers assume that data is stored in relational databases.
Roll up to increase or acquire by successive accumulations
Rolling Summary a form of storing archival data where the most recent data has the lowest level of details stored ande the older datra has higher levels of details stored.

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DataWare Housing Glossary of Terms - 'P'

Parallel Data Orgnization an arrangement of data in which the data is spread over independent storage devices and is managed independently.
Parallel Search Storage a storage device in which one or more parts of all storage locations are queried simultaneously for a certain condition or under certain parameters.
Parsing the algorithm that translates syntax into meaningful machine instructions. Parsing determines the meaning of statements issued in the data manipulation language.
Partition a segmentation technique in which data is divided into physically different units. Partioning can be done at the application or the system level.
Performance the length of time from the moment a request is issued until the first of the results of the request are received.
Periodic Discrete Data a measurement or description of data taken at a regular time interval.
Prefix Data data in a segment or a record used exclusively for system control, usually unavailable to the user.
Primitive Data data whose existence depends on only a single occurance of a major subject area of the enterprise.
Privilege Descriptor a persistent object used by a DBMS to enformce constraints on operations.
Projection an operation that takes one relation as an operand and returns a second relation that consists of only the selected attributes or columns, with duplicate rows eliminated.
Proposition a statement about entities that asserts or denies that some condition holds for those entities.

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DataWare Housing Glossary of Terms - 'O'

OLAP (On-Line Analytical Processing) Describes the systems used not for application delivery, but for analyzing the business, e.g., sales forecasting, market trends analysis, etc. These systems are also more conducive to heuristic reporting and often involves multidimensional data analysis capabilities.
OLTP (OnLine Transaction Processing) Describes the activities and systems associated with a company's day-to-day operational processing and data (order entry, invoicing, general ledger, etc.).
Operational Data Store (ODS) the form that data warehouse takes in the operational environment. Operational data stores can be updated, do provide rapid and consistent time, and contain only a limited amount of historical data.
Overflow the condition in which a record or a segment cannot be stored in its home because the address is already occupied.

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DataWare Housing Glossary of Terms - 'N'

Natural Join a join in which the redundant logic components generated by the join are removed.
Network Model a data model that provides data relationships on the basis of records or groups of records (ie. sets) in which one record is designated as the set owner, and a single member record can belong to one or more sets.
Nonprocedural Language syntax that directs the computer as to what to do, not how to do it. Typical nonprocedural languages include RAMIS,FOCUS, NOMAD, and SQL.
Normalization Normalization is a step-by-step process of removing redundancies and dependencies of attributes in a data structure. The condition of the data at completion of each step is described as a "normal form." Thus, when normalizing we talk about data as being in the first normal form, the second normal form, etc. Normalization theory identifies normal forms up to at least the fifth normal form, plus an adjunct form known as Boyce-Codd Normal Form (BCNF). The first three forms are sufficient to meet the needs of warehousing data models.

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DataWare Housing Glossary of Terms - 'M'

Main Storage Data Base (msdb) a data base that resides entirely in main storage. Such data bases are very fast to access, but require special handling at the time of update. MSDB's can only manage a small amounts of data.
Maximum Transaction Arrival Rate (MTAR) the rate of arrival of transactions at the moment of peak period processing.
MDDB Multi Dimensional DataBase
Metadata or Meta Data Metadata is data about data. Examples of metadata include data element descriptions, data type descriptions, attribute/property descriptions, range/domain descriptions, and process/method descriptions. The repository environment encompasses all corporate metadata resources: database catalogs, data dictionaries, and navigation services. Metadata includes things like the name, length, valid values, and description of a data element. Metadata is stored in a data dictionary and repository. It insulates the data warehouse from changes in the schema of operational systems.
Metadata Synchronization The process of consolidating, relating and synchronizing data elements with the same or similar meaning from different systems. Metadata synchronization joins these differing elements together in the data warehouse to allow for easier access.
Metalanguage a language used to specify other languages.
Methodology A system of principles, practices, and procedures applied to a specific branch of knowledge.
Mid-Tier Data Warehouses To be scalable, any particular implementation of the data access environment may incorporate several intermediate distribution tiers in the data warehouse network. These intermediate tiers act as source data warehouses for geographically isolated sharable data that is needed across several business functions.
Middleware A communications layer that allows applications to interact across hardware and network environments.
Migration the process by which frequently used items of data are moved to more readily accessible areas of storage and infrequently used items of data are moved to less readily accessible areas of storage.
MOLAP OLAP on Multidimensional models. In MOLAP servers, Data warehouses directly store multidimensional data in special data structures(eg.,arrays) and implement the OLAP operations over these special data structures.
Multilist Organization a chained file organization in which the chains are divided into fragments and each fragment is indexed. This organization of data permits faster access to the data.

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DataWare Housing Glossary of Terms - 'K' & 'L'

Key Compression A technique for reducing the number of bits in keys; used in making
indexes occupy less space.

Latency is often used to mean any delay or waiting that increases real or perceived response time beyond the response time desired.
Load After extracting, cleaning and transforming, data must be loaded into the warehouse. Additional preprocessing may still be required: checking integrity constraints; sorting; summarization, aggregation and other computation to build the derived tables stored in the warehouse; building indices and other access paths; and partitionaing to multiple target storage areas. Load utilities can be used for these operations.
Lockup the event that occurs when update is done against a data base record and the transaction has not yet reached a commit point.
Logging the automatic recording of data with regard to the access of the data, the updates to the data, etc.
Logical Representation a data view or description that does not depend on a physical storage device or a computer program.

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Software Project Planning - 2

Sunday, June 1, 2008

  1. Where and how are the risks associated with your project identified and documented?
  2. When you come in to the office, how do you know what you have to do during the day?
  3. How do you report the status of your project?
  4. How the team members are kept informed about the current status of the project?
  5. How do the audits cover planning activities?
  6. How does the senior management review your project's progress?
  7. How do you track the technical activities in your project? How is the status of the project communicated to the team?
  8. How do you track the size or changes to size of the work products in your project?
  9. When do revise your project plan? When do you know you have to revise your project plan? Where is the plan revision frequency documented?
  10. How do you ensure that you and all the other team members in your project have the required technical skills to execute the project?
  11. How do you assign tasks to your team members?
  12. What is the document that should be consulted to know about your project, the activities you do, your schedules and milestones?

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Software Project Planning - 1

  1. What is the project management structure in your project? Is a PL assigned to the project?
  2. How do you know that a particular individual is the project leader (or) how do you know that you are the Project Leader?
  3. What and where are the policy statements for software project planning?
  4. Explain the various activities you do (as a PL) when the project is started up.
  5. How do you know what you need to deliver or do in your project?
  6. How do you create the Software Project Management Plan (SPMP)?
  7. What training have you undergone in project planning?
  8. How do you ensure that your project plan is available for others to see? Where will you find the plans of other projects executed (in the past or currently) in the center?
  9. How did you choose the appropriate lifecycle for your project?
  10. What are the documents that you will refer to create the plan?
  11. How do you estimate the effort for your project? Where is the estimation procedure documented?
  12. What procedures do you follow to arrive at the project schedule?

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Requirements Management

  1. What is your project about? What stage or phase is it currently in? What is your current role in your project?
  2. Explain how you manage requirements in your project?
  3. Where and how do you document your requirements?
  4. What and where are the policy statements for requirement management?
  5. How do you ensure that you base your software plans, work items and products on the requirement?
  6. If during some stage down the life cycle, the initial requirements change, what will you do? How will you handle any changes in the requirements?
  7. Who reviews the requirements and the changes to the requirements?
  8. Explain the contract review process followed in your project?
  9. When requirements change, how do you handle the changes it may lead to project progress and schedule?
  10. How do you handle any risk that might arise due to changes in requirements?
  11. How do you ensure that you are consistently meeting the requirements during various stages in the life cycle of the software product?
  12. How do internal quality audits cover requirements management activities in the project?
  13. Who is responsible for managing the requirements in your project?
  14. What will you do if you find that you cannot meet the requirements?
  15. While doing HLD/LLD/Coding/Testing, how do you know that a specific HLD/LLD component, program code unit, or test case relates to a particular requirement?

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World Wide Web (WWW) , Internet Interview Questions - 2

Saturday, May 17, 2008

  1. Layers in TCP/IP
  2. Some sites work with "http://sitename.com" but for some sites we need to specify "www" - like "http://www.sitename.com". Why?
  3. Explain "URL Encoding",HTML "entity", GET method, POST method
  4. If we force XML for web design, the browzer size will reduce. How?
  5. How does DTD work?
  6. Difference between ASP and DHTML?
  7. How to create virtual directory in IIS?
  8. Can I host muliple sites on same machine?
  9. Administration of IIS.
  10. Some questions on ODBC and internet.
  11. XML and propritory databbases.
  12. Working of ping, telnet, gopher.
  13. Some questions about cross-browser compatibility.

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World Wide Web (WWW) , Internet Interview Questions - 1

  1. What is HTTP? Explain its working?
  2. What is DNS?
  3. Why do I need a domain name like 'OneSmartClick.Com'?
  4. What happens when I type in some url and press enter?
  5. How does CGI work? Can I use 'C' language to write a CGI?
  6. Working of Proxy Server, Cookies, types of cookies?
  7. What is Firewall?
  8. How to redirect to another page?
  9. Some questions on web servers.
  10. What is DOM?
  11. Connection Pooling in IIS 3.0 and 4.0
  12. What is Code Base, Style Sheets?
  13. Need for CSS
  14. DHTML: Difference between FontSize and Font Size?

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Software Quality Assurance Interview Questions

  1. What and where are the policy statements that dictate quality assurance in your project?
  2. What are the functions of the Quality Assurance Group (QAG)?
  3. How are the quality assurance activities planned ?
  4. What is a non-conformance report (NCR)?
  5. When a non-conformance is noted during these "reviews", what happens next?
  6. What is is External Quality Assurance (EQA) and Final Inspection (FI)?
  7. Is the quality assurance group (for the QAG) audited? Who does these audits?
  8. How frequently is your project audited? How do you know the result of these audits?
  9. What is an internal quality audit? What happens during this audit?

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Database Interview Questions - 2

  1. What is the use of ANALYZing the tables?
  2. How to run SQL script from a Unix Shell?
  3. What is a "transaction"? Why are they necessary?
  4. Explain Normalizationa dn Denormalization with examples.
  5. When do you get contraint violtaion? What are the types of constraints?
  6. How to convert RAW datatype into TEXT?
  7. Difference - Primary Key and Aggregate Key
  8. How functional dependency is related to database table design?
  9. What is a "trigger"?
  10. Why can a "group by" or "order by" clause be expensive to process?
  11. What are "HINTS"? What is "index covering" of a query?
  12. What is a VIEW? How to get script for a view?
  13. What are the Large object types suported by Oracle?
  14. What is SQL*Loader?
  15. Difference between "VARCHAR" and "VARCHAR2" datatypes.
  16. What is the difference among "dropping a table", "truncating a table" and "deleting all records" from a table.
  17. Difference between "ORACLE" and "MICROSOFT ACCESS" databases.
  18. How to create a database link ?

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Database Interview Questions - 1

  1. What are the different types of joins?
  2. Explain normalization with examples.
  3. What cursor type do you use to retrieve multiple recordsets?
  4. Diffrence between a "where" clause and a "having" clause
  5. What is the difference between "procedure" and "function"?
  6. How will you copy the structure of a table without copying the data?
  7. How to find out the database name from SQL*PLUS command prompt?
  8. Tadeoffs with having indexes
  9. Talk about "Exception Handling" in PL/SQL?
  10. What is the diference between "NULL in C" and "NULL in Oracle?"
  11. What is Pro*C? What is OCI?
  12. Give some examples of Analytical functions.
  13. What is the difference between "translate" and "replace"?
  14. What is DYNAMIC SQL method 4?
  15. How to remove duplicate records from a table?

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Object-Orientation Concepts, UML interview Questions - 2

  1. How do you represent static members and abstract classes in Class Diagram?
  2. Can we use UML for user interface (UI) design?
  3. Every object has : state, behavior and identity - explain
  4. How to reverse engineer C++ code in UML?
  5. What are the tools you used for OOAD?
  6. Difference: Object Oriented Analysis (OOA) and Object Oriented Design (OOD)?
  7. What are the four phases of the Unified Process ?
  8. How do you convert uses cases into test cases?
  9. Explain Class Diagram in Detail.
  10. What are the Design Patterns you know.
  11. When do you prefer to use composition than aggregation?
  12. UML: IS it a process, method or notation?
  13. Does a concept HAVE to become a class in Design?
  14. What are the good practices to use while designing for reuse?
  15. Can you think of some nice examples where *multiple* actors are associated with a use case ?
  16. How to use CRC Cards for Class Design?
  17. What is the difference between static and dynamic Classificaition.Give some examples.
  18. Explian following terms: Constraint Rules, Design by contract.
  19. What is Object Constraint Language (OCL)?
  20. Difference Between Attribute and Association.
  21. What are associative classes?

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Object-Orientation Concepts, UML interview Questions - 1

  1. What is inheritance?
  2. Difference between Composition and Aggregation.
  3. Difference: Sequence Diagrams, Collaboration Diagrams.
  4. Difference: 'uses', 'extends', 'includes'
  5. What shall I go for Package Diagram?
  6. What is Polymorphism?
  7. Is class an Object? Is object a class?
  8. Comment: C++ "includes" behavior and java "imports"
  9. What do you mean by "Realization"?
  10. What is a Presistent, Transient Object?
  11. What is the use of Operator Overloading?
  12. Does UML guarantee project success?
  13. Difference: Activity Diagram and Sequence Diagram.
  14. What is association?
  15. How to resolve many to many relationship?

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Networking, Socket Programming, Inter-Process Communication Interview Questions - 2

  1. How can I be sure that a UDP message is received?
  2. How to get IP header of a UDP message
  3. Writing UDP/SOCK_DGRAM applications
  4. How many bytes in an IPX network address?
  5. What is the difference between MUTEX and Semaphore?
  6. What is priority inversion?
  7. Different Solutions to dining philosophers problem.
  8. What is a message queue?
  9. Questions on Shared Memory.
  10. What is DHCP?
  11. Working of ping, telnet, gopher.
  12. Can I connect two computers to internet using same line ?

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Networking, Socket Programming, Inter-Process Communication Interview Questions - 1

  1. User(s) are complaining of delays when using the network. What would you do?
  2. What are some of the problems associated with operating a switched LAN?
  3. Name some of the ways of combining TCP/IP traffic and SNA traffic over the same link.
  4. What sort of cabling is suitable for Fast Ethernet protocols?
  5. What is a Class D IP address?
  6. Why do I sometimes lose a server's address when using more than one server?
  7. What is Firewall?
  8. How do I monitor the activity of sockets?
  9. How would I put my socket in non-blocking mode?
  10. What are RAW sockets?
  11. What is the role of TCP protocol and IP protocol.
  12. What is UDP?
  13. How can I make my server a daemon?
  14. How should I choose a port number for my server?
  15. Layers in TCP/IP

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Operating System Interview Questions - 1

  1. What is MUTEX ?
  2. What isthe difference between a 'thread' and a 'process'?
  3. What is INODE?
  4. Explain the working of Virtual Memory.
  5. How does Windows NT supports Multitasking?
  6. Explain the Unix Kernel.
  7. What is Concurrency? Expain with example Deadlock and Starvation.
  8. What are your solution strategies for "Dining Philosophers Problem" ?
  9. Explain Memory Partitioning, Paging, Segmentation.
  10. Explain Scheduling.
  11. Operating System Security.
  12. What is Semaphore?
  13. Explain the following file systems : NTFS, Macintosh(HPFS), FAT .
  14. What are the different process states?
  15. What is Marshalling?
  16. Define and explain COM?
  17. What is Marshalling?
  18. Difference - Loading and Linking ?

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Visual Basic (VB) Interview Questions - 3

  1. What are the ADO objects? Explain them.
  2. What are the different compatibility types when we create a COM component?
  3. What do ByVal and ByRef mean and which is the default?
  4. What does Option Explicit refer to?
  5. What does the Implements statement do?
  6. What is OLE and DDE? Explain.
  7. What is the difference between Msgbox Statement and MsgboxQ function?
  8. What keyword is associated with raising system level events in VB?
  9. What methods are called from the ObjectContext object to inform MTS that the transaction was successful or unsuccessful?
  10. What types of data access have you used.
  11. What was introduced to Visual Basic to allow the use of Callback Functions?
  12. Which controls can not be placed in MDI?
  13. Which controls have refresh method, clear method
  14. Which Property is used to compress a image in image control?
  15. Which property of menu cannot be set at run time?
  16. Which property of textbox cannot be changed at runtime and What's the maximum size of a textbox?
  17. Which tool is used to configure the port range and protocols for DCOM communications?

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Visual Basic (VB) Interview Questions - 2

  1. Draw and explain Sequence Modal of DAO
  2. How can objects on different threads communicate with one another?
  3. How can you force new objects to be created on new threads?
  4. How does a DCOM component know where to instantiate itself?
  5. How to register a component?
  6. How to set a shortcut key for label?
  7. Kind of components can be used as DCOM servers
  8. Name of the control used to call a windows application
  9. Name the four different cursor and locking types in ADO and describe them briefly
  10. Need of zorder method, no of controls in form, Property used to add a menus at runtime, Property used to count number of items in a combobox,resize a label control according to your caption.
  11. Return value of callback function, The need of tabindex property
  12. Thread pool and management of threads within a thread pool
  13. To set the command button for ESC, Which property needs to be changed?
  14. Type Library and what is it's purpose?
  15. Types of system controls, container objects, combo box
  16. Under the ADO Command Object, what collection is responsible for input to stored procedures?
  17. VB and Object Oriented Programming

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Visual Basic ( VB) Interview Questions - 1

  1. 3 main differences between flexgrid control and dbgrid control
  2. ActiveX and Types of ActiveX Components in VB
  3. Advantage of ActiveX Dll over Active Exe
  4. Advantages of disconnected recordsets
  5. Benefit of wrapping database calls into MTS transactions
  6. Benefits of using MTS
  7. Can database schema be changed with DAO, RDO or ADO?
  8. Can you create a tabletype of recordset in Jet - connected ODBC database engine?
  9. Constructors and distructors
  10. Controls which do not have events
  11. Default property of datacontrol
  12. Define the scope of Public, Private, Friend procedures?
  13. Describe Database Connection pooling relative to MTS
  14. Describe: In of Process vs. Out of Process component. Which is faster?
  15. Difference between a function and a subroutine, Dynaset and Snapshot,early and late binding, image and picture controls,Linked Object and Embedded Object,listbox and combo box,Listindex and Tab index,modal and moduless window, Object and Class,Query unload and unload in form, Declaration and Instantiation an object?

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Java Interview Questions - 3

  1. Meaning - Abstract classes, abstract methods
  2. Difference - Java, C++
  3. Difference between == and equals method
  4. Explain Java security model
  5. Explain working of Java Virtual Machine (JVM)
  6. Difference: Java Beans, Servlets
  7. Difference: AWT, Swing
  8. Disadvantages of Java
  9. What is BYTE Code?
  10. What gives java its "write once and run anywhere" nature?
  11. Does Java have "go to"?
  12. What is the meaning of "final" keyword?
  13. Can I create final executable from Java?
  14. Explain Garbage collection mechanism in Java
  15. Why Java is not 100% pure object oriented language?
  16. What are interfaces? Or How to support multiple inheritances in Java?
  17. How to use C++ code in Java Program?
  18. Difference between "APPLET" and "APPLICATION"

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C/C++ Interview Questions - 2

  1. What are inline functions?
  2. Talk some timing about profiling?
  3. How many lines of code you have written for a single program?
  4. What is “strstream”?
  5. How to write Multithreaded applications using C++?
  6. Explain "passing by value", "passing by pointer" and "passing by reference"
  7. Write any small program that will compile in "C" but not in "C++"
  8. Have you heard of "mutable" keyword?
  9. What is a "RTTI"?
  10. Is there something that I can do in C and not in C++?
  11. Why pre increment operator is faster than post increment?
  12. What is the difference between "calloc" and "malloc"?
  13. What will happen if I allocate memory using "new" and free it using "free" or allocate sing "calloc" and free it using "delete"?
  14. What is Memory Alignment?
  15. Explain working of printf.
  16. Difference between "printf" and "sprintf".
  17. What is "map" in STL?
  18. When shall I use Multiple Inheritance?
  19. What are the techniques you use for debugging?
  20. How to reduce a final size of executable?
  21. Give 2 examples of a code optimization.

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C/C++ Interview Questions - 1

  1. What is the output of printf("%d")
  2. What will happen if I say delete this
  3. Difference between "C structure" and "C++ structure".
  4. Difference between a "assignment operator" and a "copy constructor"
  5. What is the difference between "overloading" and "overriding"?
  6. Explain the need for "Virtual Destructor".
  7. Can we have "Virtual Constructors"?
  8. What are the different types of polymorphism?
  9. What are Virtual Functions? How to implement virtual functions in "C"
  10. What are the different types of Storage classes?
  11. What is Namespace?
  12. What are the types of STL containers?
  13. Difference between "vector" and "array"?
  14. How to write a program such that it will delete itself after execution?
  15. Can we generate a C++ source code from the binary file?

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J2EE Questions

Wednesday, April 30, 2008

Question: What is J2EE?
Answer: J2EE Stands for Java 2 Enterprise Edition. J2EE is an environment for developing and deploying enterprise applications. J2EE specification is defined by Sun Microsystems Inc. The J2EE platform is one of the best platform for the development and deployment of enterprise applications. This platform consists of a set of services, application programming interfaces (APIs), and protocols, which provides the functionality necessary for developing multi-tiered, web-based applications. You can download the J2EE SDK and development tools from http://java.sun.com/.

Question: What do you understand by a J2EE module?
Answer: A J2EE module is a software unit that consists of one or more J2EE components of the same container type along with one deployment descriptor of that type. J2EE specification defines four types of modules:
a) EJB
b) Web
c) application client and
d) resource adapter
In the J2EE applications modules can be deployed as stand-alone units. Modules can also be assembled into J2EE applications.


Question: Tell me something about J2EE component?
Answer: J2EE component is a self-contained functional software unit supported by a container and configurable at deployment time. The J2EE specification defines the following J2EE components:

Application clients and applets are components that run on the client.

Java servlet and JavaServer Pages (JSP) technology components are Web components that run on the server.

Enterprise JavaBeans (EJB) components (enterprise beans) are business components that run on the server. J2EE components are written in the Java programming language and are compiled in the same way as any program in the language. The difference between J2EE components and "standard" Java classes is that J2EE components are assembled into a J2EE application, verified to be well formed and in compliance with the J2EE specification, and deployed to production, where they are run and managed by the J2EE server or client container.
Source: J2EE v1.4 Glossary

Question: What are the contents of web module?
Answer: A web module may contain:
a) JSP files
b) Java classes
c) gif and html files and
d) web component deployment descriptors

Question: Differentiate between .ear, .jar and .war files.
Answer: These files are simply zipped file using java jar tool. These files are created for different purposes. Here is the description of these files:
.jar files: These files are with the .jar extenstion. The .jar files contains the libraries, resources and accessories files like property files.
.war files: These files are with the .war extension. The war file contains the web application that can be deployed on the any servlet/jsp container. The .war file contains jsp, html, javascript and other files necessary for the development of web applications.
.ear files: The .ear file contains the EJB modules of the application.


Question: What is the difference between Session Bean and Entity Bean?
Answer:
Session Bean: Session is one of the EJBs and it represents a single client inside the Application Server. Stateless session is easy to develop and its efficient. As compare to entity beans session beans require few server resources.

A session bean is similar to an interactive session and is not shared; it can have only one client, in the same way that an interactive session can have only one user. A session bean is not persistent and it is destroyed once the session terminates.

Entity Bean: An entity bean represents persistent global data from the database. Entity beans data are stored into database.


Question: Why J2EE is suitable for the development distributed multi-tiered enterprise applications?
Answer: The J2EE platform consists of multi-tiered distributed application model. J2EE applications allows the developers to design and implement the business logic into components according to business requirement. J2EE architecture allows the development of multi-tired applications and the developed applications can be installed on different machines depending on the tier in the multi-tiered J2EE environment . The J2EE application parts are:

a) Client-tier components run on the client machine.
b) Web-tier components run on the J2EE server.
c) Business-tier components run on the J2EE server and the
d) Enterprise information system (EIS)-tier software runs on the EIS servers


Question: Why do understand by a container?
Answer: Normally, thin-client multi-tiered applications are hard to write because they involve many lines of intricate code to handle transaction and state management, multithreading, resource pooling, and other complex low-level details. The component-based and platform-independent J2EE architecture makes J2EE applications easy to write because business logic is organized into reusable components. In addition, the J2EE server provides underlying services in the form of a container for every component type. Because you do not have to develop these services yourself, you are free to concentrate on solving the business problem at hand (Source: http://java.sun.com/j2ee/1.3/docs/tutorial/doc/Overview4.html ).

In short containers are the interface between a component and the low-level platform specific functionality that supports the component. The application like Web, enterprise bean, or application client component must be assembled and deployed on the J2EE container before executing.


Question: What are the services provided by a container?
Answer: The services provided by container are as follows:
a) Transaction management for the bean
b) Security for the bean
c) Persistence of the bean
d) Remote access to the bean
e) Lifecycle management of the bean
f) Database-connection pooling
g) Instance pooling for the bean


Question: What are types of J2EE clients?
Answer: J2EE clients are the software that access the services components installed on the J2EE container. Following are the J2EE clients:
a) Applets
b) Java-Web Start clients
c) Wireless clients
d) Web applications

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JavaScript Objective Questions

Thursday, April 10, 2008

  • Code: JavaScript
    /* start code */
    function getNum(x)
    {
    x += 3;
    if(x)
    return x;
    x *= 3;
    return x;
    }

    What will the above decalred function return when called like this getNum(4); ?

    a> 9
    b> 7
    c> 21
    d> 8
  • Which company first implemented the JavaScript language?
    a> Netscape Communications Corp.
    b> Microsoft Corp.
    c> Sun Microsystems Corp.
    d> Consortium of the above companies
  • When was the first release of a browser supporting JavaScript?
    a> 1994
    b> 1995
    c> 1996
    d> 1997
  • The original name of JavaScript was
    a> JavaScript
    b> LiveScript
    c> WireScript
    d> ECMAScript
  • The JavaScript international standard is called
    a> ECMA-262 Standard
    b> DHTML JavaScript Standard
    c> JavaScript 1.3 Standard
    d> ISO-262 Standard
  • Which of the following statements best describes the relationship between JavaScript and DHTML?
    a> JavaScript is DHTML plus CSS plus Document Object Model.
    b> DHTML is Document Object Model plus JavaScript plus CSS.
    c> Document Object Model is JavaScript plus DHTML plus CSS.
    d> JavaScript has nothing to do with DHTML.
  • What label catches all values except those specified in “switch” statement?
    a> otherwise
    b> default
    c> any
    d> all
  • How do you locate the first X in a string txt?

    a> txt.find('X');
    b> txt.locate('X');
    c> txt.indexOf('X');
    d> txt.countTo('X');
  • Which of these contains an executable statement?
    a> // var a = 0; // var b = 0;
    b> /* var a = 0; // var b = 0; */
    c> /* var a = 0; */ var b = 0;
    d> // var a = 0; /* var b = 0; */
  • What does ++ operator do?
    a> Adds two numbers together
    b> Joins two text strings together
    c> Adds 1 to a number
    d> Adds 2 to a number
  • Which of the following does not result in a variable going out of scope?
    a> End of the block in which it was defined
    b> Start of a block in which a like named variable is defined
    c> when a function is called
    d> when the program finishes running
  • Which of these is not a logical operator?
    a> &&
    b> &
    c>
    d> !
  • What does the following statment return, Math.floor(29.36); ?
    a> 30
    b> 29.5
    c> 29
    d> 29.4
  • Code: JavaScript
    /* start code */
    var a = ["s","a","v","e"];
    document.write(a.join(""));

    What would be the output of the above code fragment?
    a> undefined
    b> save
    c> vase
    d> s
  • /* start code */
    var a = 0;
    var b = 1;
    var c = a b;

    What does the variable c contain??
    a> 0
    b> true
    c> false
    d> null
  • What would be the output of the follow statement, document.write("JavaScript ".length); ?
    a> 9
    b> 10
    c> 11
    d> null

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Java Interview Questions - 2

Tuesday, March 18, 2008

  • Suppose if we have variable ‘I’ in run method, if I can create one or more thread each thread will occupy separate copy or same variable will be shared?
  • Tell some latest versions in JAVA related areas?
  • What are JVM.JRE, J2EE, JNI?
  • What are Normalization Rules? Define Normalization?
  • What are abstract classes?
  • What are adapter classes?
  • What are advantages of java over C++?
  • What are benefits if Swing over AWT?
  • What are byte codes?
  • What are files generated after using IDL to java compiler?
  • What are session variable in servlets?
  • What are statements in Java?
  • What are streams?
  • What are swing components?
  • What are traverses in binary tree?
  • What are virtual functions?
  • What do you know about garbage collector?
  • What do you mean by light weight and heavy weight components?
  • What do you mean by multithreading?
  • What is JAR file?
  • What is JFC?
  • What is JNI?
  • What is base class for all swing components?
  • What is client server computing?
  • What is constructor and virtual function? Can we call virtual function in constructor?
  • What is corresponding layout for card in swing?
  • What is difference abstract class and interface?
  • What is exact difference in between Unicast and Multicast object? Where will it be used?
  • What is functionability stubs and skeletons?
  • What is functionality of stub?
  • What is interface?
  • What is layout for toolbar?
  • What is light weight component?
  • What is main functionality of Prepared Statement?
  • What is main functionality of remote reference layer?
  • What is mapping mechanism used by java to identify IDL language?
  • What is middleware? What is functionality of web server?
  • What is polymorphism?
  • What is protocol used by server and client?
  • What is role of Web Server?
  • What is root class for all java classes?
  • What is serializable interface?
  • What is serialization?
  • What is thread?
  • What is update method called?
  • What is use of interface?
  • What is user defined exception?
  • When will you use interface and abstract class?
  • Where are card layouts used?
  • Why do we use oops concepts? What is its advantage?
  • Why do you canvas?
  • Why does java not support multiple inheritance?
  • Why is java not fully objective oriented?
  • Why is java not pure oops?
  • Why java is considered as platform independent?
  • Why there are some null interface in JAVA? What does it mean? Give some null interface in JAVA?
  • Write down how will you create Binary tree?
  • Write program for recursive traverse?
  • what is meant wrapper classes?

Read more...

Java Interview Questions - 1

  • Can you load server object dynamically? If so what are 3 major steps involved in it?
  • Can you run product development on all operating systems?
  • Considering notepad/IE or any other thing as process, What will happen if you start notepad or IE 3 times ? Where three processes are started or three threads are started?
  • Difference : AWT and Swing?
  • Difference : Abstract class and Interface?
  • Difference : Grid and Gridbaglayout?
  • Difference : Process and Thread?
  • Difference : java and c++?
  • Difference : process and threads?
  • Does java support function overloading, pointers, structures, unions or linked lists?
  • Does java support multiple inheritance? if not, what is solution?
  • Explain 2-tier and 3-tier architecture?
  • Explain about version control?
  • Have you ever used HashTable and Directory?
  • How can two threads be made to communicate with each other?
  • How can we do validation of fields in project?
  • How can you know about drivers and database information ?
  • How do you download stubs from Remote place?
  • How does thread synchronization occur in monitor?
  • How java can be connected to database?
  • How will you add panel to frame?
  • I want to store more than objects in remote server? Which methodology will follow?
  • In container there are 5 components. I want to display all component names, how will you do that?
  • In htm form I have button which makes us to open another page in seconds. How will you do that?
  • In htm page form I have one button which makes us to open new page in seconds. How will you do that?
  • Is there any tag in htm to upload and download files?
  • Meaning of Servelet? What are parameters of service method?
  • Meaning of Session? Explain something about HTTP Session Class?
  • Meaning of Static query and Dynamic query?
  • Meaning of class loader? How many types are there? When will we use them?
  • Meaning of cookies? Explain main features?
  • Meaning of distributed application? Why are we using that in our application?
  • Meaning of flickering?
  • Meaning of function overloading and function overriding?

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C Interview Questions - 8

  • What is the output of printf("%d")
  • What will happen if I say delete this
  • What is Dangling pointer?
  • Difference between "C structure" and "C++ structure".
  • Diffrence between a "assignment operator" and a "copy constructor"
  • What is the difference between "overloading" and "overridding"?
  • Explain the need for "Virtual Destructor".
  • Can we have "Virtual Constructors"?
  • What are the different types of polymorphism?
  • What are Virtual Functions? How to implement virtual functions in "C"
  • What are the different types of Storage classes?
  • What is Namespace?
  • What are the types of STL containers?.
  • Is there any difference between a messageand method?
  • If I ask you to write 'VI' editor in C++ - How you'll proceed?
  • Difference between char name[] = “mindgrill q”; and char *name = “mindgrill q”;
  • Should we use global variables?
  • Parsing HTML or XML document with C++
  • What is 'self assignment'?
  • Difference between how virtual and non-virtual member functions are called
  • Finding shortest path aka Dijkstra's algorithm and backtracking
  • Doing permutations and combinations in C++
  • Difference between "vector" and "array"?
  • How to write a program such that it will delete itself after exectution?
  • Can we generate a C++ source code from the binary file?
  • What are inline functions?
  • Talk sometiming about profiling?
  • How many lines of code you have written for a single program?
  • What is "strstream" ?
  • How to write Multithreaded applications using C++?
  • Explain "passing by value", "passing by pointer" and "passing by reference"
  • Write any small program that will compile in "C" but not in "C++"
  • Have you heard of "mutable" keyword?
  • What is a "RTTI"?
  • Is there something that I can do in C and not in C++?
  • Why preincrement operator is faster than postincrement?
  • What is the difference between "calloc" and "malloc"?
  • What will happen if I allocate memory using "new" and free it using "free" or allocate sing "calloc" and free it using "delete"?
  • What is Memory Alignment?
  • Explain working of printf.
  • Difference between "printf" and "sprintf".
  • What is "map" in STL?
  • When shall I use Multiple Inheritance?
  • What are the techniques you use for debugging?
  • How to reduce a final size of executable?
  • Give 2 examples of a code optimization.

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C Interview Questions - 7

  • What is linklist and why do we use it when we have arrays? - I feel correct answer should be linklist is used in cases where you don’t know memory required to store data structure and need to allocate is dynamically on demand.
  • What is maximum combined length of command line arguments including space between adjacent arguments?
  • What is near, far and huge pointers? How many bytes are occupied by them?
  • What is object file? How can you access object file?
  • What is pointer?
  • What is recursion?
  • What is similarity between Structure, Union and enumeration?
  • What is static identifier?
  • What is structure?
  • What is use of typedef?
  • When reallocating memory if any other pointers point into same piece of memory do you have to readjust these other pointers or do they get readjusted automatically?
  • Where are auto variables stored?
  • Where does global, static, local, register variables, free memory and C Program instructions get stored?
  • Write down equivalent pointer expression for referring same element a[i][j][k][l]?
  • advantages of using pointers in program?
  • advantages of using typedef in program?
  • bit fields? What is use of bit fields in Structure declaration?
  • declare following:
    array of three pointers to chars,
    array of three char pointers,
    pointer to array of three chars,
    pointer to function that receives int pointer and returns float pointer,
    pointer to function that receives nothing and returns nothing
  • detect loop in linked list?
  • differences between malloc() and calloc()?
  • differences between structures and arrays?
  • different storage classes in C?
  • dynamically allocate one-dimensional and two-dimensional array of integers?
  • enumerations?
  • implement substr() function that extracts sub string from given string?
  • macros? advantages and disadvantages?
  • obtain current time and Difference : two times?
  • obtain segment and offset addresses from far address of memory location?
  • print string on printer?
  • register variables? advantage of using register variables?
  • that function should be used to free memory allocated by calloc()?
  • that header file should you include if you are to develop function that can accept variable number of arguments?

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C Interview Questions - 6

  • How can called function determine number of arguments that have been passed to it?
  • How can we check whether contents of two structure variables are same or not?
  • How can we read/write Structures from/to data files?
  • How much maximum can you allocate in single call to malloc()?
  • How will you declare array of three function pointers where each function receives two ints and returns float?
  • If we want that any wildcard characters in command line arguments should be appropriately expanded, are we required to make any special provision? If yes, that?
  • In header file whether functions are declared or defined?
  • In header files whether functions are declared or defined?
  • Increase size of dynamically allocated array?
  • Increase size of statically allocated array?
  • Out of fgets() and gets() that function is safe to use and why?
  • Program : compare two strings without using strcmp() function.
  • Program : concatenate two strings.
  • Program : find Factorial of number.
  • Program : generate Fibonacci Series?
  • Program : interchange variables without using third one.
  • Program : s for String Reversal. same for Palindrome check.
  • Program : that employs Recursion?
  • Program : that uses command line arguments.
  • Program : that uses functions like strcmp(), strcpy(), etc.
  • To that numbering system can binary number be easily converted to?
  • Use bsearch() function to search name stored in array of pointers to string?
  • Use functions fseek(), freed(), fwrite() and ftell()?
  • Use functions memcpy(), memset(), memmove()?
  • Use functions randomize() and random()?
  • Use functions sin(), pow(), sqrt()?
  • Use qsort() function to sort array of structures?
  • Use qsort() function to sort name stored in array of pointers to string?
  • What advantages of using Unions?
  • What do functions atoi(), itoa() and gcvt() do?
  • What do ‘c’ and ‘v’ in argc and argv stand for?
  • What does error ‘Null Pointer Assignment’ mean and what causes this error?
  • What does static variable mean?
  • What is NULL Macro? Difference : NULL Pointer and NULL Macro?
  • What is NULL Pointer? Whether it is same as uninitialized pointer?
  • What is far pointer? where we use it?

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Chitika

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