1. Keep it short and simple
  2. One problem per message, please
  3. No explanations of the problem. Just post a one liner of what you think should be said in the error message. Link to another thread if you truly feel the need to expound on the problem
  4. The point of this thread is to improve the quality of error messages, not provide people insights into your problems
  5. Do not post if you don't have a solution to the problem. This is not a tech support thread, this is a compendium of problems with solutions
  6. Scan the thread to see if a similar exception/error message is already posted. Only add a new post on your problem if the problem occurs under a situation not previously outlined, and you have a solution to this situation/problem
    • In other words, if it happens to you, but other solutions didn't resolve your problem, do not post here -- this is not a tech support thread.

  7. If the exception generates a message, make sure you include that
    • In cases where the error message uses details from your schema/architecture, add a very short explanation as to what the elements in the error message represent (dimension/hierarchy/level names, members of a dimension, measures, etc)

  8. If a stack trace is available, whether or not there's a message, paste only the first few lines of the stack trace -- enough to determine where the exception is generated from.
  9. If there are multiple distinct exceptions generated from one problem (note rule #2), include each distinct exception, following rules 4 & 5

Down the road, with the blessing of the Mondrian devs, I hope to use the information people post here to improve the quality of the error messages Mondrian generates. Please -- I can't stress this enough -- keep it short and simple. I don't want to read about your trials & problems, I want to see something like the following:

Error message: WARN [ExplicitRules] The Cube 'blah' relation is not a MondrianDef.Table but rather 'mondrian.olap.MondrianDef$View'.
Stack trace: None available
Suggested error message: "Mondrian does not support <View>, <Join>, or <InlineTable> for fact tables -- only <Table> is supported at this time"
Short explanation: Error message is good enough.