How to query historic values using Open Data Access
First I have sucessfully configured Open Data Access from 800xA for Real-time data so that I can read certain data from an Reactor object by performing a SQL query on ODA Tables I have created in SQL Server Management Studio.
Now my problem is that according to the manual I should be able to find historical data in the Numericlog and Messagelog tables in the ABBODA database, but when I query theese tables the query only returns the headings and no data.
In my test system (System_800xA_5.1_FP4_Demo_Backup_Kit) I have several Log Configurations configured as OPC Single Logs and if I select an OPC_5s_5h log and then click the Status tab I can Read the values logged that has the headings Index, Time, Value and Quality.
I have IM installed on the test node and a PLC Generic Control Network with a history source.
What can I have missed during my setup that prevents me from accessing or storing the logged data in the Numericlog and Messagelog tables?