infosys technical interview questions

Infosys Software Technology

Technical Interview Question-Answers

1.What are the 4 basics of OOP?

• Abstraction, Inheritance, Encapsulation, and Polymorphism.

2.What you mean by Object Relational DBMS?

• An object-relational database (ORD), or object-relational database management system (ORDBMS), is a database management system (DBMS) similar to a relational database, but with an object-oriented database model: objects, classes and inheritance are directly supported in database schemas and in the query language. In addition, just as with proper relational systems, it supports extension of the data model with custom data-types and methods.

3. Structural difference between bitmap and b-tree index ?

4.what is database Schema?

• The formal definition of database schema is a set of formulas (sentences) called integrity constraints imposed on a database.

5.what are the different levels of database schema?

• Conceptual schema- a map of concepts and their relationships.
• Logical schema- a map of entities and their attributes and relations
• Physical schema- a particular implementation of a logical schema
• Schema object- Oracle database object

6. what is difference between foreign key and reference key ?

• Reference Key is the primary key that is referenced in the other table (linked via the other tables Foreign Key). Foreign Key is how you link the second table to the primary tables Primary Key (or Reference Key).

7. Tell me about DSN?

• A Data Source Name (DSN) is the logical name that is used by Open Database Connectivity (ODBC) to refer to the drive and other information that is required to access data. The name is used by Internet Information Services (IIS) for a connection to an ODBC data source, such as a Microsoft SQL Server database. To set this name, use the ODBC tool in Control Panel.
• click->start in control panel->double click Administrative Tool->click ODBC data source->click System DSN tab->click Add

8.Difference between Clustered index and non clustered index ?

• Clustered Index
• Only one per table
• Faster to read than non clustered as data is physically stored in index order
• Non Clustered Index
• Can be used many times per table
• Quicker for insert and update operations than a clustered index

9 What is the difference between an EXE and a DLL?

• The term EXE is a shortened version of the word executable as it identifies the file as a program. On the other hand, DLL stands for Dynamic Link Library, which commonly contains functions and procedures that can be used by other programs.

10.Scenarios in which web application should be used and desktop application should be used?

11.Tell how to check whether a linked list is circular.

• Create two pointers, each set to the start of the list. Update each as follows:

while (pointer1) {
pointer1 = pointer1->next;
pointer2 = pointer2->next; if (pointer2) pointer2=pointer2->next;
if (pointer1 == pointer2) {
print ("circular\n");
}
}

12.Why is it difficult to store linked list in an array?

13.what is the difference between socket and session?

14.What is a default gateway?

15.What is SMTP?

16.What is an interrupt?

17.What is debugger?

18.What port does telnet use?

19.Given an array of 1s and 0s arrange the 1s together and 0s together in a single scan of the array. Optimize the boundary conditions.

20.Define Data Abstraction. What is its importance?