Many database application vendors are finding that their products are at a critical point in the product life cycle. They have released with a solid level of success several versions that use indexed sequential access method (ISAM)–based database management systems (DBMS) like Btrieve.
However, due to rapidly expanding customer needs and the powerful capabilities of relational database management systems (RDBMS) offerings, many Independent Software Vendors (ISVs) are now converting their applications to RDBMSs. Applications based on an RDBMS can offer better performance and scalability, and more replication features than ISAM-based solutions. Well-designed RDBMS solutions vary in size from a few megabytes to multiple terabytes.
Microsoft SQL Server 7.0 is a powerful and flexible RDBMS solution. The ease of use and scalability of SQL Server 7.0 has made it attractive for thousands of application developers. This chapter presents a strategy that will allow you to convert Btrieve applications to work with SQL Server. The strategy presents many of the features of SQL Server that make it a high-performance alternative to an ISAM platform. While the Btrieve platform is this chapter’s focus, the chapter introduces many concepts that can be applied to any ISAM-based application.
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The Btrieve environment may seem simpler to use and administer than SQL Server. However, this simplicity comes at a price. Btrieve has several architectural shortcomings that add complexity to applications that access it. Btrieve does not:
The Microsoft strategy is to make SQL Server the easiest database for building, managing, and deploying business applications. This means providing a fast and efficient programming model for developers, eliminating database administration for standard operations, and providing sophisticated tools for more complex operations.
| SQL Server 7.0 feature | Description |
|---|---|
| Administration Wizards | Many new wizards simplify advanced tasks such as creating databases, scheduling backups, importing and exporting data, and configuring replication. |
| DBA Profiling and Tuning Tools | New tools provide advanced profiling and tuning:
· SQL Server Profiler improves debugging by allowing the capture and replay of server activity. · Index Tuning Wizard provides guidance through the index tuning process. · SQL Server Query Analyzer allows easy, in-depth query analysis. |
| Distributed Management Objects | Independent software vendors and corporate developers can easily develop custom management applications. The COM-based framework exposes all management interfaces for SQL Server. Automation components and custom applications can be written using the Microsoft Visual Studio development system, the Microsoft Visual Basic development system for Applications, and Java scripting. |
| Dynamic Self-Management | Reduces need for DBA intervention: memory and lock resources are adjusted dynamically; file sizes grow automatically; autotuning features guarantee consistent performance under variable-load conditions. |
| Event/Alert Management | Enhances ability to monitor performance, availability, and security status through policy-based event management. Improved alert management provides automatic notification and recovery in response to thresholds and severity levels. |
| Job Scheduling and Execution | The job scheduling and execution environment is extended to allow stand-alone, multiserver, single-step, multistep jobs and job step with dependencies. Great flexibility is provided though a variety of scripting environments: Microsoft Visual Basic Scripting Edition, Java scripting, Microsoft Windows NT commands and custom ODBC and OLE DB programs. |
| Multisite Management | Improves power and flexibility for managing multiple servers. Drag-and-drop and single commands can be used to implement changes across groups of servers. Management is simplified through the use of a repository that maintains schema, profiles, and data transformation metadata for all servers in the enterprise. |
| Security | Security administration is improved and simplified through better integration with Windows NT security and SQL Server roles. Windows NT integration includes authentication, support for multiple groups, grant/revoke/deny permission management activities and dynamic use of groups. |
| Standards Compliance | Full compliance with the ANSI/ISO SQL-92 Entry-level standards. Views are included for the ANSI/ISO schema information tables as defined in SQL-92, providing a standard method for metadata examination. |
| Version Upgrade | Databases are easily transferred from version 6.x to 7.0, via a fully automated upgrade utility. Customers are able to get up and running quickly on the new version and take advantage of new features with minimal impact on operations. |
| Visual Data Modeler | New tools provide a graphical interface for building and managing schema and other database objects. |