Thank you Oleg.
What Oleg mentioned is true and applies to SAP BW OLAP connector. It seems you are using SQL Connector so, you should be fine.
In next steps, you may want to check ST22, SM21 and SM37 transaction to see if you find error logs, dumps or any job cancellations.
Also please post your SAP Basis version and transports you have imported in your system.
And if you can provide versions of SAP R/3, QV and SAP Connector, that would be helpful.