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In general, load report dropdown list retrieves all the available report collections from database. Each report collection may having multiple reports.
The report list dropdown list found in toolbar shows the available reports from the currently loaded report collection from the database.
This is the default behavior of our control.
If the above information is not sufficient, Kindly provide us more details about your requirement and if possible provide us screen-shot/video corresponding to the requirement. Also provide us the data source(relational or OLAP) used to render the control and operational mode(server mode or client mode) of the control and Essention Studio version that you are using. These informations would be helpful for us to proceed further