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SQL Tutorial

Introduction Select Selecet Distinct Where And,Or,Not Order By Insert Into Null Values Update Delete Select Top Min and Max Count,Avg,Sum Like Wild Cards In Between Aliases Joins Group By Having Exists Any all Select Into Comment Operations
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SQL Introduction


Structure Query Language(SQL) is a database query language used for storing and managing data in Relational DBMS. SQL was the first commercial language introduced for E.F Codd's Relational model of database. Today almost all RDBMS(MySql, Oracle, Infomix, Sybase, MS Access) use SQL as the standard database query language. SQL is used to perform all types of data operations in RDBMS.


What is SQL?

1.SQL stands for Structured Query Language
2.SQL lets you access and manipulate databases
3.SQL became a standard of the American National Standards Institute (ANSI) in 1986, and of the International Organization for Standardization (ISO) in 1987


What Can SQL do?

1.SQL can execute queries against a database
2.SQL can retrieve data from a database
3.SQL can insert records in a database
4.SQL can update records in a database
5.SQL can delete records from a database
6.SQL can create new databases
7.SQL can create new tables in a database
8.SQL can create stored procedures in a database
9.SQL can create views in a database
10.SQL can set permissions on tables, procedures, and views,

SQL is a Standard - BUT

Although SQL is an ANSI/ISO standard, there are different versions of the SQL language.
However, to be compliant with the ANSI standard, they all support at least the major commands (such as SELECT, UPDATE, DELETE, INSERT, WHERE) in a similar manner.


SQL Statements

Most of the actions you need to perform on a database are done with SQL statements.
Each SQL statement begins with any of the SQL keywords and ends with the semicolon (;). The semicolon is used in the SQL for separating the multiple Sql statements which are going to execute in the same call. In this SQL tutorial, we will use the semicolon (;) at the end of each SQL query or statement.


Example

This SQL statement reads the data from the SQL database and shows it as the output to the database user.

SELECT "column_name" FROM "table_name";

Here, column....are the field names of the table you want to select data from. If you want to select all the fields available in the table, use the following syntax


Using SQL in Your Web Site

To build a web site that shows data from a database, you will need: 1)An RDBMS database program (i.e. MS Access, SQL Server, MySQL)
2)To use a server-side scripting language, like PHP or ASP
3)To use SQL to get the data you want
4)To use HTML / CSS to style the page