Refering to Partitioned Tables and Indexes in SQL Server 2005:
SQL Server 2005 offers a way to easily and consistently manage large tables and indexes through partitioning, which allows you to manage subsets of your data outside of the active table. This provides simplified management, increased performance, and abstracted application logic, as the partitioning scheme is entirely transparent to the application.
Read the provided article to learn the best practices about tables partitioning in sql server.
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