If I understand you right, you want to execute the 'sp_spacesused' stored procedure ? You can use the 'OpenAccessContextBase.ExecuteNonQuery' method to call the procedure. Note that calling this method will start a transaction. Since the procedure performs a read-only operation you can call context.ClearChanges() after ExecuteNonQuery to rollback the transaction.
Do get back in case you need further assistance.
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