MicroStrategy 7 Administrator Guide

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• Join options, such as the star join and full outer join
• Metric calculation options, such as when to check for NULLs and zeros
• Pre-and-post SQL statements
• Query optimizations, such as sub queries and driving tables
• Table types, such as temporary tables or derived tables
Default VLDB properties are set based on the database type specified in the
database instance. Updates for the default settings may be made available
periodically as database vendors add new functionality.
For more information about VLBD properties, see the following appendix:
Appendix B: VLDB Properties
Database connection caching
Connecting to and disconnecting from databases incurs a small amount of
overhead that may cause a small yet noticeable decrease in performance in highconcurrency
systems. With connection caching, MicroStrategy Intelligence
Server is able to reuse database connections. This minimizes the overhead
associated with repeated connecting to and disconnecting from databases.
Connections may exist in one of two states:
• busy: connections that are actively submitting a query to a database
• cached: connections that are still connected to a database but not actively
submitting a query to a database
A cached connection will be used for a job if the following criteria are satisfied:
• The connection string for the cached connection must match the connection
string that would be used for the job.
• The execution mode matches synchronous versus asynchronous.
,PSRUWDQWÃMicroStrategy Intelligence does not cache any connections that
have pre-or- post SQL statements associated with them because these options may
drastically alter the state of the connection.
To learn about...
...the editors, wizards, and monitors used to configure and manage database
connectivity, see the following Interfaces topics:
14 Chapter 2 Database Connectivity