Chapter 10 - Retrieving and Storing Data in Databases
Visual Basic Developers Guide to ASP and IIS
A. Russell Jones
Copyright 1999 SYBEX Inc.
Understanding ADO
ADO is a flexible method of retrieving and storing data not only in relational databases, but also in text files, spreadsheets, directories—any type of data store for which someone has written an Object Linking and Embedding Database (OLEDB) driver, called a provider in ADO-speak. Microsoft introduced ActiveX Data Objects (ADO) version 1 with IIS 3 and ASP pages. They have continued to extend the technology, which is now at version 2.1, soon to be 2.5.
Microsoft is committed to ADO. I expect that ADO will gradually supplant other methods of database access, because it's easy to learn and to use.
The main advantages of ADO are that it has:
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A simple and relatively flat object model
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Consistent syntax across all data stores
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The capability for disconnected and persistent recordsets
Many programmers—especially those using Access and FoxPro databases—avoided ADO until recently. Earlier versions of ADO provided SQL Server programmers with access to the database objects through DDL but did not provide easy ways to program Access database objects. That's changed with version 2.1, which includes the ADOX that contain the equivalents of Table, QueryDef, Index, and other intrinsic database objects.