OLAP interfaces, or Online Analytical Processing, is an older Microsoft standard for connecting to business data in multi-dimensional arrays.
The OLAP interface is made up of a Web service and two SQL scripts (GetCurrentData.sql and GetTrendData.sql).
The SQL scripts each use four fields, two of which are used in your KPIs:
- LookUp (this is the tag name)
- Value (this is the value associated with the tag name)
The other two fields are used to find the correct value.
- SampleData (the table name)
- lupd (the date/time the row was last updated)
These are generic field names.
How Visual KPI Reads Data with OLAP Interfaces
When displaying KPI values from OLAP interfaces, Visual KPI reads the tag name associated with a specific KPI column (such as Value, Target, Low, etc.) and then searches the SampleData table for a row that has the same name in the LookUp column. When the interface finds the correct row, it retrieves the Value in the same row and returns that value to Visual KPI.
When displaying a KPI’s trend, Visual KPI reads the tag name associated with a specific KPI column (such as Value, Target, Low, etc.) and then searches the SampleData table for each row that has the same name in the LookUp column and where the lupd (timestamp) falls within the correct time range. Time range is based on the current Trend Range in Visual KPI. When the interface has completed its search, it retrieves the Value and lupd(timestamp) in the same row and returns these to Visual KPI, which in turn, draws the trend graph.
Using Visual KPI Server Manager to Set Up ODBC Interfaces
To use OLAP interfaces with Visual KPI, you need to specify the connection parameters for your database and modify the SQL Scripts to reference the actual field names for SampleData, LookUp, Value, and lupd. Visual KPI Server Manager allows you to make these changes during installation of OLAP interfaces. Should you need to modify the connection parameters after the interface has been installed, use Visual KPI Server Manager to make the changes.
If you want to test the OLAP interface before you connect it to your live database, you can create and work with the SQL Demo database.