Technology Questions

The UTL_FILE database package can be used to read and write operating system files. You need to have read /write access rights in that directory before the package can be used.

Example to write file:

Fhandler is a variable of type UTL_FILE.FILE_TYPE

UTL_FILE.PUTF(fHandler, 'Im writing to a file\n');

Example to read file:

UTL_FILE.GET_LINE(fHandler, buf);

- A web worker is a JavaScript which runs in the background. It exists in external files. 

 - It is independent of other scripts and does not affect the performance of the page. 

 - Web workers are usually used for CPU intensive tasks.

ABAP (Advanced Business Application Programming) is a high level programming language created by the German software company SAP. It is currently positioned as the language for programming SAP's Web Application Server, part of its NetWeaver platform for building business applications. Its syntax is somewhat similar to COBOL.

- The principle of least privilege is used to provide more security to the computer programs. 

- The principle allows the designing of the program such that any unauthorized access is not allowed and only the person who owns the program will be able to access it. 

- The services provided should be able to access only those products that need the services. 

- Web servers that are involved in responding the queries of the web users provide only accessing to the HTML files that will serve the purpose of the programs. 

- Computer programs should be made such that it provides secure features of logging into the program with proper authentication.

When creating a thread by extending the Thread class, it is not mandatory to override the run method (If we are not overriding the run method , it is useless), because Thread class have already given a default implementation for run method. But if we are implementing Runnable , it is mandatory to override the run method. The preferred way to create a thread is by implementing Runnable interface, because it give loose coupling.

Pseudo elements allow the use of the part of element and not the element itself. They are applied to block level element, which is used for the complete block for which the CSS is being written. This allow the subpart of an element to be styled like paragraphs and headings. For example:

selector:pseudo-element {property:value;}

p: first-line {text-transform: lowercase;}

It adds the style to the first line of the code in the paragraph.

Cursors help you manipulate the information retrieved by select statements. This can be done by assigning a name to the cursor.

Example:

CURSOR emp_cur 

IS 

SELECT emp_number from employee_tbl where employee_name = name_in;

Types of Cursors:

Implicit cursors- These cursors are not declared by the programmer. They are issued when the SQL statement is executed. The open, close and fetching is done by itself.

Example:

UPDATE employee SET salary = salary * 2.1;

Here, an implicit cursor is issued to identify the set of rows in the table which would be affected by the update.

Explicit cursors- These cursors are defined by programmer. They are used in queries that return multiple rows.

Example:

CURSOR emp_cur 

IS 

SELECT emp_number from employee_tbl where employee_name = name_in;

JavaScript:

- JavaScript is a scripting language developed by Netscape Communications.

- The Netscape Navigator interprets JavaScript embedded into Web pages.

- JavaScript is used for developing web applications.

- It is not dependent on Sun Microsystem's Java language.

JScript:

- Microsoft JScript is an open implementation of Netscape's JavaScript.

- JScript is a scripting language designed to create active online content. ActiveX controls, Java programs, etc can be linked and automated in the web pages using JScript.