The Evolutionary Development of SQL Server Database Technology-Part 1

1. The Origins of SQL and Relational Databases (1970s – 1980s)

1.1 The Birth of Relational Database Theory

In the early 1970s, Dr. Edgar F. Codd, a researcher at IBM, introduced the concept of the Relational Database Model in his seminal paper, A Relational Model of Data for Large Shared Data Banks. This laid the foundation for modern database management systems (DBMS).

1.2 The Development of SQL

Structured Query Language (SQL) was developed in the mid-1970s at IBM as part of the System R project, aimed at implementing Codd's relational model. SQL quickly became the standard language for querying and managing relational databases.

1.3 The Rise of Commercial Relational Databases

By the late 1970s and early 1980s, companies like Oracle, IBM, and Sybase began developing commercial relational database management systems (RDBMS) that implemented SQL. Microsoft would later enter the market through a partnership with Sybase.

2. The Early Years of Microsoft SQL Server (1989 – 1994)

2.1 Microsoft and Sybase Partnership

In 1989, Microsoft, Sybase, and Ashton-Tate collaborated to release SQL Server 1.0 for OS/2, marking Microsoft's entry into the database market. This version was essentially a rebranded Sybase SQL Server.

2.2 SQL Server 4.2 – The Transition to Windows

With the release of SQL Server 4.2 in 1992, Microsoft introduced support for Windows NT, setting the stage for future database development independent of Sybase.

2.3 The End of the Microsoft-Sybase Partnership
By 1994, Microsoft and Sybase ended their partnership, with Microsoft taking full control over SQL Server's development for Windows platforms.

3. The Rise of Microsoft SQL Server (1995 – 2000)

3.1 SQL Server 6.0 – The First Fully Microsoft-Controlled Version
Released in 1995, SQL Server 6.0 was the first version fully developed by Microsoft. This marked a turning point, with significant performance and scalability improvements.

3.2 SQL Server 7.0 – A Major Overhaul

SQL Server 7.0 (1998) was a complete rewrite of the database engine, introducing key features such as:
A new storage engine
Integrated OLAP services
Improved query optimization
GUI-based management tools