This manual was compiled by Project A Web Development as a project supported by Jim Teece. It was written by Ethan Townsend as a documented means of migrating our ADO ASP application, SIB (Site­in­a­box), from Microsoft SQL Server 7.0 to an open source database. SIB is a large database­ driven application that includes many views, stored procedures, and complex SQL executed from the ASP pages.

The primary goals were to:
1) Modify the application so that it could seamlessly switch between the existing SQL Server database and the new open source database.
2) Have the ability to offload existing databases from SQL Server to the new database server.
3) Make no modifications to the existing, working SQL Server.
4) Maximize ease­of­use, stability, performance, and security.

The following open source database servers were installed and analyzed to determine their feasibility in replacing SQL Server:
? MySQL 4.1: The stable version of MySQL at the time of testing.
? MySQL 5: The development version of MySQL.
? PostgreSQL 7.4:
? PostgreSQL 8.0.3:
? Firebird 1.5.3:
? MaxDB 7.5:
? MaxDB 7.6:

After reviewing the alternatives, we settled on PostgreSQL 8.0 for the following reasons:
? Good documentation,
? Best performance on Windows platform (using the included ODBC driver).
? Custom operators and functions allowed a compatibility layer to minimize code changes (only about 300 changes were necessary in 700,000 lines of code).
? Easy to install and use (a GUI was included and the installer was straightforward)

Download pdf Conversion of Microsoft SQL/ASP applications to PostgreSQL