Slow report caused by 85K record dataset

Question

I'm developing a report that cross validates fields in the Item table, based on criteria-FILTERS. I have 30 such FILTERS.
Item Table is all about Item SKU properties and has Fields like: group, category, colour, price, cost, brand,class, etc
Filters should cross validate the fields that has not been set properly, for example: For category field = ABC , group field <> class field.
The output of each filter expected to be 5-50 records (possible mismatches) 
My initial plan was
Use full  big single  dataset -  85K records x 20 fields  from  Item table NOT FILTERED
Create 30 Tablixes in the report and APPLY FILTERS on Tablix level 
After  creating 3 tablixes with filters, my report 's become very slow.
QUESTION: for the better performance is it better to use 1 big dataset, 30 tablixes will reuse this dataset but apply own filters , each filter expected to be 5-50 records (my initial plan).
OR create 30 datasets and each dataset would return  5-50 records ???

Answer 1

Hi BrBa,
As per my understanding, I think the second plan that create 30 datasets and each dataset returns 5-50 records can improve the report performance. The reasons are as follows:
There are 85k records in your database, while only about 1000 records are needed. If we use the first plan, we should add a lot of filters on the tablix. This would spend much more time than directly filter the values using SQL server database engine.
Additional, if you need all 85k records, maybe the first pane would be better. Because SQL server database engine can quickly retrieve the data using table scan, it still needs a lot of filters on the tablix. But in the second plan, it needs good enough
quick search method. This would depends on your data.
The following document about Troubleshooting Reports: Report Performance is for your reference:
http://technet.microsoft.com/en-us/library/bb522806(v=sql.105).aspx
If there are any other questions, please feel free to ask.
Regards,
Katherine Xiong
Katherine Xiong
TechNet Community Support