Hello,
You can select only wanted fields by doing following steps
1)Go to Tools-> Data Connections->select the Connection and Click on Modify
2)Now Check only those fields which you want to querry
or
1)You can do so by opening the Repeating table properties->Change binding-> Select Datasource-> select repeating table in the tree structure below and adding the fields you want to query.
I hope this helps you.
Kalyan G Reddy
Infopath MVP 2007 and 2008