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Lesson 4 SQL-92
Objective Introduction to SQL-92?
With all the power of the Structured Query Language to retrieve information, several key software vendors figured out that it would be smart to use this approach for queries. It quickly became apparent that a standards committee was needed to determine what the standard is and how to apply it.
The ANSI standards group is charged with standardizing the language elements that make up SQL.
The current accepted revision is SQL-92, which is what you will typically find implemented in different mainstream products.


What is important to understand about the standard is that there is one.
The language steps and statements that you learn that relate to SQL, by and large, will be applicable across mainstream database applications.
One of the leverage points for SQL is the fact that you can use what you know on more than one platform.
This is not to say that there are not any differences between platforms. Vendors typically take the standard and extend it to provide enhanced data services that they believe are necessary to serve their customer base. Things that will change may include minor variances in how you refer to information in your query and how the information is returned to you when the results have been determined.

It gives them a light to steer by, a direction to follow. The extensions developed are just that. They are extensions to the underlying database capabilities. The standard language elements and approach remain intact.
In the next lesson, we will take a look at dialect variations.