What is SQL?

What is SQL? SQL stands for Structured Query Language and is the lingua franca in the database world. SQL is a standard that is used by all database vendors and programmers to define, extract and access the information that is stored in databases. SQL began life as an IBM creation but was standardized by the American National Standards Institute (ANSI) and the International Organization for Standardization (ISO) as ANSI/ISO SQL in 1988. Since then ANSI/ISO SQL standard continued to evolve. The ANSI-SQL group has since published three standards over the years:

1. SQL89 (SQL1)

2. SQL92 (SQL2)

3. SQL99 (SQL3)

SQL is a query language. It is English-like and easy to use. However, although there are more than 90 SQL reserved words, most programmers seldom use more than the following handful of commands - SELECT, INSERT, UPDATE, DELETE, FROM, WHERE, HAVING, BETWEEN, LIKE, OR, AND, NOT, IN, ORDER, GROUP and BY.

For example, if you had a database table named "employees" and you wanted to retrieve all records where the employee has the last name "goodman", you would use the following SQL statement:

SELECT * FROM employees WHERE lastname = 'goodman';

There are many different categories of SQL statements but the basic ones which all programmers should be familiar with are the SQL statements that:

1. Create tables and manipulate their definitions

2. Query the table data

3. Manipulate the table data

SQL is predominantly used by 2 types of users - programs and humans (keying in the commands through a database client) - to pass instructions to databases. SQL commands can be keyed into a database client like the MySQL Query Browser or the SQL Server Enterprise Manager and executed to either return a result or modify records in the database. SQL can also be used in conjunction with programming language or scripting language like Microsoft Visual Basic or PHP to communicate with the database.

Although SQL is a world standard, it is unfortunate that most database vendors have come up with different dialects and variations. This is because every database vendor wants to differentiate their database products from the crowd. One good example is Microsoft SQL Server's TRANSACT-SQL. TRANSACT-SQL is a superset of SQL and is designed for use only with Microsoft SQL Server. Although it does make programming much easier for software developers, it is not compliant with other databases like Oracle or MySQL - making TRANSACT-SQL programs non database-portable. As such, although many of these features are powerful and robust, it is good practice to exercise caution and limit your SQL use to be compliant with the ANSI/ISO SQL standards and ODBC-Compliant.

Courtesty of SQLPrimer.com. For more information, please contact the Webmaster of SQLPrimer.com - http://www.sqlprimer.com.

In The News:

Bulletin Board  Deccan Herald
Web Developer - ThinkMarkets  Built In Chicago
Revving the Engine  IndustryWeek
Web hub offers resources on COVID-19's impacts  Marshalltown Times Republican

High Quality Website at Low Cost

Although designing a great web site is an important part... Read More

Art, Artists, and the Web:Part: 2--First Steps in Building an Artist?s Website

What you should do and know if you are an... Read More

Why Is No-one Buying From My Website?

Are you, like many other website owners, frustrated at the... Read More

The Road to Better Results

A lot has changed in the way sites are optimized... Read More

Website Globalization

Globalize Your WebsiteThe Internet has unlocked a wide array of... Read More

Create Huge Income From Your Web Site - 10 Easy Ways

The cost of setting up a web site is dirt... Read More

The 5 Biggest Mistakes Almost All Web Designers Make

Huge Mistake #1: Creating a Website with Flash -- Did... Read More

You Don?t Have to be Amazon.com to Achieve 12% Conversion Rates!

That's right. According to a recent study by Nielsen/NetRatings, Amazon.com... Read More

How to Promote Your Law Firm Website On the Internet for Maximum Profit

Making maximum profit from your law firm website is important,... Read More

Link Trades That Waste Your Time

Never has competition been so difficult in the Internet world.... Read More

Things to Consider Before Starting a Website

In the time that I have been using the Internet,... Read More

Frequent Business Question: How Do You Start a Web Business?

Today it seems everyone is jumping on the entrepreneur bandwagon,... Read More

3 Reasons Why You Need URL Rewriting Module To Enchance Your Web

URL rewriting are major needs for your sites that produce... Read More

Easy Steps To Website Development and Promotion

One of the most important parts of establishing a new... Read More

How to Make Your Own Website For Free

If you like the Internet and surfing through the billions... Read More

Increase Hits to Help Increase Your Business

In this day and age most businesses consider having their... Read More

Why Your Business Needs a Website

Even with the steady growth of the World Wide Web,... Read More

Website Imperatives and Solutions

When you take a look at the most visited sites... Read More

7 Profit Producing Reasons Why Every Successful Service Professional Needs A Web Presence

Your business website is a critical aspect of being able... Read More

Top 10 Webmaster Challenges

Webmasters deal with a myriad of complex design challenges every... Read More

Web Accessibility: The Basics

What is web accessibility & why is it important?Web accessibility... Read More

Beyond Web Usability: Web Credibility

If you've been developing websites on Mars for the past... Read More

A Network Of Web Sites Is Not Enough!

The big thing these days is your ability to capture... Read More

Make Your Communication Come Alive

Design and layout can make your communication come alive and... Read More

Make Your Own Brand!

There are millions and millions of websites on the Internet.... Read More