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.
![]() |
|
![]() |
|
![]() |
|
![]() |
Alternate medicine finds its own place in the hearts and... Read More
Think up a name and check if yourname.com is available.... Read More
--------------------------------Why Should You Create a website?--------------------------------A. What do you want... Read More
Yahoo has long offered email, an online calendar, notes, bookmarks,... Read More
Fantastico is a 3rd-party cPanel add-on and can be purchased... Read More
Losing website sales and traffic is sometimes simply a case... Read More
The big thing these days is your ability to capture... Read More
A PHP Redirect automatically transfers a web user from one... Read More
There was a time not long ago when setting up... Read More
When most people build a web site, they think one... Read More
Are bloated images slowing down your web site and causing... Read More
With the New Year upon us yet again, it's time... Read More
Have you ever wondered what challenges are faced by other... Read More
"I have a small business with just a couple of... Read More
What to do if you are an artist after you... Read More
Why do some sites succeed while the vast majority of... Read More
Many web developers today are starting to KISS their website,... Read More
Building a website and getting it online is easy. Driving... Read More
1. Upload robots.txt file in to your root directory and... Read More
The growth in Internet usage around the world is astounding... Read More
When building a relationship, listening is more important than talking.A... Read More
Getting a Targeted Visitor to a website is a waste... Read More
There are millions and millions of websites on the Internet.... Read More
The cost of setting up a web site is dirt... Read More
"What's in it for me?" you ask. "Why should I... Read More
Understanding and using web analytics.In recent years, website marketers were... Read More
The first step in setting up an online business...Starting an... Read More
We all start out the same. Some have budgets, some... Read More
Profiles are one of the best kept secrets around regarding... Read More
If you like the Internet and surfing through the billions... Read More
Making maximum profit from your law firm website is important,... Read More
You have seen those web pages where they have the... Read More
Making a web site is easy. Making a good web... Read More
There are hundreds of millions of Web surfers today. Each... Read More
Losing website sales and traffic is sometimes simply a case... Read More
How do you decide on the content, products and or... Read More
"If you build it, they will come"; is an age... Read More
Whether you have your own business already, or are looking... Read More
Often time I've browsed sites and seen the same thing... Read More
How popular is online shopping? And is there room for... Read More
The internet is a sea of knowledge. Getting your information... Read More
Many millions of dollars are being wasted on promoting and... Read More
D.zigns dzignerwebs The Basics Before starting on... Read More
Absolutely everything stems from the purpose of your website -... Read More
Build it and they will come is not always true;... Read More
If you've been developing websites on Mars for the past... Read More
The Internet has opened a whole New World of opportunity... Read More
Every good Internet business understands the value of conversions versus... Read More
The Internet is a remarkable publishing medium. With just a... Read More
You know exactly what your organisation does and what your... Read More
Starting a business online is no longer as difficult as... Read More
Right after the thought, "I need a website," people usually... Read More
As increasing numbers of people search for information on the... Read More
Everyday thousands of new businesses make the leap and take... Read More
In the late 1990's three San Francisco based web developers... Read More
The needs of screen magnifier users are overlooked when implementing... Read More
I've heard several prominent web marketers mention in their classes... Read More
One of the most important parts of establishing a new... Read More
While studying online for IT investment opportunities, I found that... Read More
When visitors add your web site to their Favorites or... Read More
Fantastico is a 3rd-party cPanel add-on and can be purchased... Read More
The Internet is being used by local service business to... Read More
RIVERSIDE, CA August 4, 2004 ?- "Historically, small business owners... Read More
We are clearly well past the innocent "golden age" of... Read More
In this day and age most businesses consider having their... Read More
Making a web site is easy. Making a good web... Read More
Web Development |