Technology Questions

When a class is derived from another class, then the members of the base class become the members of the derived class. The access modifier used while accessing members of the base class specifies the access status of the base class members inside the derived class.

The syntax to inherit a class from another class in C# is as follows:
class MyNewClass : MyBaseclass

A sequence is a database object that is used to generate sequential number.

CREATE SEQUENCE seqname [increment] [minimum value][maximum value][start][cache][cycle]               Nextval and currval lets us get the next value and current value from the sequence.

An index is a object which is used to improve performance during retrieval of records.

CREATE [UNIQUE] INDEX index_name 

ON employee[emp_id, emp_name,dept_id]

[COMPUTE STATISTICS]

The UNIQUE keyword is used when combined values of the index should be unique.

The COMPUTE STATISTICS during the creation of index optimizes the plan of execution of the SQL statement and improves performance.

- A web page with large number of images takes a longer time to load. This is because each image separately sends out a http request.

- The concept of CSS sprite helps in reducing this loading time for a web page by combining various small images into one image. This reduces the numbers of http request and hence the loading time.

- A clustered index is a special type of index that reorders the way records in the table are physically stored. Therefore table can have only one clustered index. The leaf nodes of a clustered index contain the data pages.

- A non clustered index is a special type of index in which the logical order of the index does not match the physical stored order of the rows on disk. The leaf node of a non clustered index does not consist of the data pages. Instead, the leaf nodes contain index rows.

An application behaves differently when running in foreground than in background because of the limitation of resources on iOS devices.

Client code must use setters and getters to access internal data in DataHiding

The dba_insert() function adds a record to a database.