Technology Questions

Q:

When do you use UPDATE_STATISTICS command?

Answer

This command is used when a large processing of data has occurred. If any large amount of deletions, any modifications, or Bulk Copy into the tables has occurred, it has to update the indexes to take these changes into account. UPDATE_STATISTICS updates the indexes on these tables accordingly.


 

Report Error

View answer Workspace Report Error Discuss

Subject: SQL

0 2940
Q:

What is the common usage of serialization? What exceptions occur during serialization?

Answer

The object need to be serialized when it’s sent over a network and when it’s state is saved. Exceptions which occur during serialization are:


a. transient fields


b. when the base class is serialized then only base class fields are handled.


c. static fields are ignored because they are not part of any state.

Report Error

View answer Workspace Report Error Discuss

Subject: Java

1 2936
Q:

How do you eliminate duplicate values in DB2 SELECT?

Answer

Use SELECT DISTINCT ..... in DB2 query


 


The DISTINCT keyword can be used to return only distinct (different) values.


Syntax:


     SELECT DISTINCT column1,column2


      FROM table_name;


 

Report Error

View answer Workspace Report Error Discuss

0 2934
Q:

A data warehouse is composed of

A) current data B) internal and external data sources
C) historical data from legacy systems D) historical & current data
 
Answer & Explanation Answer: C) historical data from legacy systems

Explanation:

A data warehouse is a relational database that is designed for query and analysis rather than transaction processing. It usually contains historical data that is derived from transaction data, but it can include data from other sources. Data warehouses are designed to help you analyze your data.

Report Error

View Answer Report Error Discuss

Filed Under: Oracle
Job Role: Database Administration , IT Trainer

3 2934
Q:

What is the difference between a Hub and a Switch?

Answer

Hub is device to connect two devices, switch is a network bridge which processes and routes data approirately over network layer of OSI Reference model

Report Error

View answer Workspace Report Error Discuss

0 2930
Q:

Why static method can not call non static method of the same class?

Answer

bcoz the static method does not contains the 'this' reference.

Report Error

View answer Workspace Report Error Discuss

Subject: Java

0 2928
Q:

What is Test Harness?

Answer

“In software testing, a test harness or automated test framework is a collection of software and test data configured to test a program unit by running it under varying conditions and monitor its behavior and outputs. It has two main parts: the test execution engine and the test script repository.”


 

Report Error

View answer Workspace Report Error Discuss

Subject: QA Testing

0 2926
Q:

How are documents accessed and manipulated in XML?

Answer

The XML DOM (document object model) is used the access and management of xml. It is a platform that is language neutral and allows a program or a script to dynamically access a document. It also allows the updation of content as well as the structure and style of the document. It is responsible for the defining of the object and properties of all xml elements as well as to define the methods for their access. There are various methods that can be used in xml dom such as:


- getElementsByTagName: used to call a specific user defined tag.


- setAttribute: used to change the value of an existing attribute.


- appendChild: used to add a child node to another node.


 

Report Error

View answer Workspace Report Error Discuss

Subject: Web Technology

1 2925