JetSQL » Introduction

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Welcome to the DevGuru Jet SQL Quick Reference guide. This is an informative 40 page reference source that explains and gives examples of code for the clauses, declarations, expressions, functions, operators, and statements used by Jet SQL.

The Structured Query Language (SQL) is a computer language for accessing and manipulating databases. The fundamental concept is to think of the data as being stored in one or more tables. When a request is made to retrieve data from these tables, which is called a "query", the resultant output is also presented in as table. There are many different versions of the SQL language, but to be in compliance with the ANSI SQL '92 Standard, they must use and support the same major keywords in a similar manner (such as SELECT, UPDATE, DELETE, INSERT, WHERE, and others).

The version of SQL created by Microsoft is called Jet SQL and it is the database engine behind Microsoft's Access.

Jet SQL has certain limitations compared to the other versions of SQL. In general, Jet SQL is not designed to manage a database, but rather, it is used to retrieve information from a database. To cite two limitations, Jet SQL, by itself, cannot create a database and cannot manage security . This is where the Microsoft Data Access Object, commonly called DAO, enters the scene. DAO contains libraries which are designed to manage databases. While, yes, you can use Jet SQL without DAO, you are effectively limiting your options to handle the data. For example, with DAO you can create a database and manage security. Likewise, Microsoft's Access offers the ability to create and maintain databases.

The value of Jet SQL (and DAO) is that it allows the developer to add databases to an active Web site.