Analysis Services Partitioning Issue
I have a Measure Group, that is partitioned daily. I can process a particular partition, and the XMLA command completes successfully. Furthermore, I have ensure at least one partition is processed for every Measure Group, therefore my cube is "partially processed" and I should be able to browse it.
The problem... no data can be seen in the cube for any of the Measures within this Measure Group. What is really driving me crazy is that I can capture the SQL command that SSAS is executing against the server, and it returns rows开发者_运维知识库! Yet sure enough, when I check the properties of the partition I just processed, it says it's size is 0.0 MB. It also has no slice, don't know if that helps.
If anyone has seen anything like this and has any idea... I am all ears.
You must set a partition slice. That is how SSAS determines that the data should reside in that partition. Without the slicer it is discarding the rows read. Check out http://sqlcat.com/technicalnotes/archive/2007/09/11/ssas-partition-slicing.aspx for example.
Your immediate problem is unlikely to be because of the missing slices. As Mosha explains it here, defining slicing details for partitions is very important for performance reasons. Here is a quote from him:
If the data slice value for a partition is set properly, Analysis Services can quickly eliminate irrelevant partitions from the query processing and significantly reduce the amount of physical I/O and processor time needed for many queries issued against MOLAP and HOLAP partitions
Without the data slice, Analysis Services cannot limit a query to the appropriate partitions and must scan each partition even if zero cells will be returned.
The above says that if partition slices are not defined, then SSAS will not be able to optimize certain queries by scanning only from the relevant partitions. But it also says that with no slices defined it should still return the correct results, albeit probably much slower. As a side-note, it is also implied that if slices ARE defined BUT improperly, then it could happen that wrong results get returned, or nothing at all.
Since your partitions have no slices defined, rather the problem somehow must be with the SQL query bindings used for creating the partitions. Have you checked that the data source is configured correctly in SSAS? When you were running the query manually you might have been connected to a different SQL server instance than the one configured for the SSAS cube (e.g. UAT vs. PROD).
精彩评论