InfoPath Dev

Thanks Greg to reply me.But I can't understand how i put the rule or set it at design time in the data source task pane.Please give me full detail of set default value of database driven dropdown. Thanks.  

Sir I have a problem in my InfoPath form having a dropdown which is filled by database.How can i set a default value in dropdown? Please help meThanks  

Thanks Hilary to reply me, please check this and reply me. I need the solution very urgent. Thank you again.

Sir i am new in InfoPath 2007.I have a problem that in my InfoPath form has a control repeating table with two columns as Item Name and Item Rate.When user fills value in a row successfully and inserts another row then previously inserted rows are becomes read only.Please help me to solve this problem.