This example illustrates how to interpret the messages found in the MDEX Engine error log.

Suppose the following messages appear in your MDEX Engine error log:

ERROR 06/04/08 18:13:33.250 UTC DGRAPH {dgraph}: Bad dimension or property name 
[WineType] in select

To troubleshoot, look through the corresponding MDEX request log for entries that contain “select” and “WineType”. The results are as follows:

1212603213 127.0.0.1 - 3378 105.54 7.49 200 56300 -2 10 
/graph?node=0&select=P_Name+P_Score+WineType&group=0&offset=0&nbins=10&pred=
P_Score%7CGTEQ+70&irversion=510

Check the documentation in this section for the select parameter that appears in the MDEX Engine URL, in the request log. You will find that it corresponds to the Java API ENEQuery.setSelection() method; there is no corresponding UrlENEQuery URL parameter. This means that the incorrect value is set through this method. You can now look through the application code and find the setSelection() call to try to determine why it is specifying an incorrect property or dimension name as part of the value for this method. In this example, it is because the code is specifying "WineType" rather than "Wine Type" with a space.