Technology Questions

- A status occurs when image copy on a table needs to be taken

- The table is available only for queries and can not be updated

- COPY PENDING status can be removed by taking away the image copy or by using REPAIR utility

The classloader is a subsystem of JVM that is used to load classes and interfaces.There are many types of classloaders e.g. Bootstrap classloader, Extension classloader, System classloader, Plugin classloader etc.

Use Case: A use case is a description of the process which is performed by the end user for a particular task. Use case contains a sequence of step which is performed by the end user to complete a specific task or a step by step process that describe how the application and end user interact with each other. Use case is written by the user point of view.

Use case Testing: the use case testing uses this use case to evaluate the application. So that, the tester can examines all the functionalities of the application. Use case testing cover whole application, tester performs this testing in step by step process to complete one task

Marquee tag: Marquee tag is used when we want that some text or content move in the web page whether horizontally or vertically. 

Syntax of Marquee tag: <marquee>content you want to move</marquee>

Attribute of Marquee tag are: bgcolor, direction, height, width, vspace etc.

- Fail-safe approach defines the level that divides the security such that it is safe even in case the system is failed.

- The fail safe approach doesn’t allow an attacker to take the advantage by breaking in the system and crashes out.

- This approach allows the web server to perform the routines even if the system runs out of the memory in case of any attack. 

- The system in attacks doesn’t skip the access to the control check or it doesn’t skip serving any document requested. 

- Fail safe approach can force the web server to run of the memory and have a DoS attack.

1 : InnoDB provides us row level locking while MyISAM provides us table level locking.

2 : InnoDB offers foreign key constraints wheres in MyISAM does not have foreign key constraints.

3 : InnoDB does not have full text search wheres MyISAM provides us full text search.

Oracle supports 3 transaction isolation levels: 

- Read committed (default)

- Serializable transactions

- Read only

- 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.

- 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.