I have around 36 partitions in the 2005 cube. Each partition is roughly 20M fact rows.
The partitions are differentiated by a date member dimension.
When I run a query which selects by a distinct date, SSAS tries to scan all partitions (for inclusions?). This introduces a huge performance impact. It takes many seconds to run a single query.
I have aggregations designed specifically for relevant dimensions. The Profiler shows that SSAS reads from aggregations. It does not read from facts.
The storage mode is MOLAP.
Do I need to use the partition slice property ? I am seeing on forums from time to time that this attribute is not used in MOLAP.
I just need to make sure that my queries are fast.
I don't see where it could hurt to set this property, though BOL indicates this is only used by SSAS for ROLAP partitions. I thought I had heard that with MOLOP and/or HOLAP, that SSAS maintained an internal set of information regarding the contents of a slice that would handle this function for you. Maybe someone else out there could chime in on this one.
Regarding the query you specify above, are you specifying a date member from the specific cube dimension used to partition your cube? You probably are but it wasn't explicitly stated. Date dimensions are often used in a role-playing capacity which introduces some confusion.
Thanks,
Bryan
can anyone clarify if the Slice property on Partition is used in MOLAP or not?
I checked info....xml files for my slicing dimension min/max values and they seem correct, however with explicit queries, SSAS still reads a bunch of partitions...
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