Picking a Dimension for an MDC Table
MDC tables can deliver incredible performance advantages over regular tables. However, when defining MDC tables, you must give careful consideration to dimension selection. Having too granular of a dimension (e.g., customer number) could cause too few individual records to have their own blocks of like information—the worst case would be if that information is unique. Clearly this would not benefit from any performance benefits of an MDC table, and would have excessive space requirements.
When choosing dimensions for a table, consider the fact that you are enabling fast query access, so the best place to start is by looking at your expected queries. Columns in equality or range queries, as well as those with ...
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