Technical Questions Answers » Data Base

What is Transact-SQL?

admin — Wed, 07 Nov 2007 20:09:47 +0000

SQL Server uses Transact-SQL, a version of the Structured Query Language (SQL), as its database query and programming language. SQL is a set of commands that allows you to specify the information that you want to retrieve or modify. With Transact-SQL, you can access data and query, update, and manage relational database systems.

The American National Standards Institute (ANSI) and the International Standards Organization (ISO) have defined standards for SQL. Transact-SQL supports the latest ANSI SQL standard published in 1992, called ANSI SQL-92, plus many extensions to provide increased functionality

What is a Relational Database Management System (RDBMS)?

admin — Wed, 07 Nov 2007 20:09:01 +0000

A relational database is a collection of data organized in two-dimensional tables consisting of named columns and rows. Each table represents the mathematical concept of a relation as defined in set theory. In set theory, columns are known as attributes and rows are known as tuples. The operations that may be performed on tables are similarly based on manipulation of relations to produce new relations, usually referred to as queries or views.

Relational databases differ from non-relational databases in that the database user is not aware of system dependencies that may be stored within the data. No knowledge of the underlying database is required; data can be queried and updated using standard languages (these languages together make up SQL) that produce a consistent result. SQL Server databases are relational.

An RDBMS is responsible for:

Storing and making data available in tables.
Maintaining the relationships between tables in the database.
Ensuring the integrity of data, by making sure that rules governing the data values and defining the relationships between tables are not violated.
Recovering all data to a point of known consistency in case of a system failure.

What is Client/Server Database Model?

admin — Wed, 07 Nov 2007 20:02:00 +0000

The terms client/server can be used to refer to very general concepts or specific items of hardware or software. Technically, it refers to any two cooperating processes.

Aclient is any component of a system that requests services or resources from other system components.

A server is any system component that provides services or resources to other system components.

For example, when you print a document from your workstation on a network, the workstation is the client and the print spooling machine is the server.

In a client/server model, the database server is responsable for the following:

Processing data modification and retrieval requests.
Performing data-intensive processing.
Enforcing all database rules and constrains.
Enforcing data security.

In a client/server model, the database client is responsable for the following:

Presenting the data to the user in an easily and useful format.
Providing an interface to the various tools, data, and reports.
Submitting requests to the server.

What is SQL Server?

admin — Mon, 08 Oct 2007 19:12:52 +0000

Microsoft SQL Server or MSSQL is a powerfull client/server relational database management system (RDBMS) produced by Microsoft. SQL Server is based on the ANSI SQL 92 standard and it is a complete database system.

SQL Server helps you build, deploy, and manage enterprise applications. At the center of SQL Server is the SQL Server engine, which processes the database commands. The process runs inside Windows and understands only connections and SQL commands.