Hi,
I have a problem with processing my cube. My fact table (with telephone data) contains about 400,000 records... which is increasing rapidly (400,000 records is about 8 months of data)...
I have a few dimensions:
Dimension User: about 200 records
Dimension Line: about 200 records
Dimension Direction: 4 records
Dimension Date: 365 records for each year
Dimension TimeInterval: with 24 intervals
So far so good... when I process this dimension I have no problem....
However, when I add a dimension (CalledNumber, with exactly 101 records) the processing hangs as soon as it starts...
The SQL performed when processing the cube looks like this:
[CODE]
SELECT field1, field2,... fieldn
FROM table1, table2,.... tablem
WHERE
(table1.id=table2.table1id)
AND
(table2.id=table3.table2id)
...
[/CODE]
When I execute above SQL in the Query Analyser from SQL Server Enterprise Manager, it ALSO hangs...
I am not really suprised by that, because this SQL first create a huge table of 400,000 x 200 x 200 x 4 x 365 x 24 x 101 records and after that works through the WHERE statements to filter out the appropriate records.
for me it would be more logical to use the following code to process the cube, but that cannot be changed in Analysis Manager:
[CODE]
SELECT field1, field2,... fieldn
FROM table1
LEFT JOIN table2 ON (table1.id=table2.table1id)
....
LEFT JOIN tablem ON (tablem.id = tablem-1.tablemid)
[/CODE]
When I execute above SQL in the Query Analyser from SQL Servel Enterprise Manager, it does NOT hang, but performs the query in about 35 seconds....
But Analysis Manager does not allow me to change the SQL used for processing the cube...
What can I do to add more dimensions to my cube... (It will be more anyway after adding the CalledNumber dimension)?
any suggestions?
PS. forgot to mention: I use Sql Server 2000
For people who have the same problem... on another forum I got an answer (Thanks Darren Gosbell) which gave me the solution:
http://msdn.microsoft.com/library/default.asp?url=/library/en-us/olapdmad/agoptimizing_1qr7.asp
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