June 18, 2008

SQL Definition

Full form:  Structured Query Language.
Pronounced as: "S-Q-L" or "see-quill".
Originally developed by: IBM in 1970 for its mainframes.
Support: All database systems designed for client/server environments support SQL.
Usage: It used to interrogate and process data in a relational database.

SQL commands can be used to interactively work with a database or can be embedded within a programming language to interface to a database.Computer programming language used for retrieving records or parts of records in databases and performing various calculations before displaying the results. SQL is particularly suitable for searching relational databases. It has a formal, powerful syntax and is able to accommodate logical operators. Its sentence-like structure resembles natural language except that its syntax is limited and fixed.

Types of SQL Commands:  
  •     Data Definition Language (DDL)
  •     Data Manipulation Language(DML)
  •     Data Query Language(DQL)
  •     Data Control Language(DCL)
  •     Data Administration  Commands
  •     Transactional Control Commands
SQL can perform:
  •   SQL can execute queries against a database
  •    SQL can retrieve data from a database
  •    SQL can insert records in a database
  •    SQL can update records in a database
  •    SQL can delete records from a database
  •    SQL can create new databases
  •    SQL can create new tables in a database
  •    SQL can create stored procedures in a database
  •    SQL can create views in a database
  •    SQL can set permissions on tables, procedures, and views
SQL Versions:
  •    SQL Server 2012 
  •    SQL Server 2008 R2
  •    SQL Server 2008
  •    SQL Server 2005
  •    SQL Server 2000
  •    SQL Server 7
  •    SQL Server 6.5