We are using Crystal Reports 10 with an Oracle 10 database. Some of the reports have used the Visual Linking expert to join two tables together. One of these tables is actually a materialized view. For the most part this seems to be working. However we recently ran into a situation where the report was not returning any data for one particular set of parameters (this is the only reported issue, there could be more). I could take the SQL query that is generated from Show SQL Query option and run it in SQL Navigator and it returned the one row that was expected. Even more perplexing I created a new report using a Command object and pasted the same SQL in it and it returned the one row expected. Has anyone run into similar issues using materialized views? I don't really understand how they work. Should all our reports (about 10 of them) that use this materialized view be changed to use a command object? If so I guess the more basic question is why does using a command object seem to work and just letting crystal create the SQL doesn't.