This example demonstrates how Geo SCADA Expert might be configured to query data in an Oracle database, using the Value Lookup Method.
An Oracle database includes the following database table:
Table Name: SCADADATA
|
ValueId |
Value |
Time |
|---|---|---|
|
1 |
2.5 |
10:00 |
|
2 |
3.7 |
10:00 |
|
3 |
11.3 |
10:00 |
|
3 |
11.4 |
09:00 |
|
3 |
10.2 |
08:00 |
The timestamps are in UTC.
Within Geo SCADA Expert, an ODBC Query is configured to retrieve the ValueId, Value and Time columns of data from the SCADADATA table.
To do this, the ODBC Query is configured to use this SQL query request:
Within Geo SCADA Expert, an ODBC Analog point is configured to return data from the rows in the ValueId column that have a value of 3. To do this, the point is configured to use a Value Lookup Method with these settings:
As the Use All Results check box is selected, this results in the ODBC Analog Point being given the values of 10.2, 11.4, and then 11.3 respectively. (These are the values retrieved, in ascending timestamp order, from the entries in Lookup Column 1 (‘ValueId’) that have a Lookup Value of 3. The point values are retrieved from column 2 (as Value Column = 2) and the timestamps from column 3 (as Timestamp Column = 3).)