Technology Questions

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.

1) START- Used to run a SQL script.
2) ACCEPT- Accepts input from user.
3) GET- Gets the sql file from user to place in buffer.
4) LIST- Displays the last command executed.
5) RUN- Used to list and run the command in buffer
6) SHOW- Shows the environment settings. Example: SHOW PAGESIZE

A struct is a special C data type that encapsulates other pieces of data into a single cohesive unit. Like an object, but built into C.

PROBLEMS:

i) If the user forgets to opt for keep session then the session will be automatically removed from the session queue(log remains). However if session is processed we may delete it manually.

ii)if session processing fails data will not be transferred to SAP database table.

FIND_GROUP(function) FIND_COLUMN(function)

SQL Server is having a fantastic feature to retrieve data persisted in the form of XML format. The data in the XML format can be retrieved using FOR XML clause appending to the SELECT statement.

It offers 3 modes.

- “FOR XML AUTO": Returns XML elements that are nested, based on which tables are listed in the "from" part of the query, and which fields are listed in the "select" part.

- "FOR XML RAW": Returns XML elements with the "row" prefix (ex: ""). Each column in a table is represented as an attribute and null column values aren't included.

- "FOR XML EXPLICIT": Explicit mode is the most complex shaping method used in SQL Server 2000. It allows users to query a data source in such a way that the names and values of the returned XML are specified before the query batch is executed. 

Web server handles client side and server side validations and helps to deliver web content that can be accessed through the Internet protocols.

Examples:

Microsoft IIS (Internet Information Service)

Apache web server from Apache

Java web server

Pramathi web server etc...

XML, Extensible Markup Language, is an open, text based markup language that provides structural and semantic information to data. XML is a metalanguage that can be used to create other language. It is used to structure and describe data that can be understood by other applications. Using XML, we can separate the user interface from data.

Features of XML :

- XML is a generalized markup language that means one can define his/her own tag sets.

- A valid XML document contains rules and is self-describing.

- The rules that are found in DTD allow the documents to be validated.