Please refer to the post in your support ticket on the same question:
"...You can implement your own parameter controls and search functionality inside your application and then pass the selected parameter values directly to the report parameters.
Also note that if you try to load 30000+ data rows in a report parameter you may face some performance issues, so this is not recommended in general....
Using the above approach will allow you to use custom loading of the values to avoid loading all records at once. The values can be sent to the report as in the How To: Pass values to report parameters
If you have further questions, let us continue the discussion in your support ticket to keep a better track of the exchanged information.
Thank you for your understanding.
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