how do i pass an parameter to setFilter() through a variable

[babusunlux]

hai

I am using QDataTable to display the data from the database with three fields which has the following data types.
Channel Name as char, Chval as int and GenDateTime as datetime in mysql, i have set the database connection and the data has been displayed in the qdatatable, but i want to set the setfilter() so the i am can apply the where option.

If i pass the the value directly in the is format setFilter("ChName=\"1AE01A\"") it works fine but how do i pass through some variable.
Say QString Vname="1AE01A"
setFilter("ChName =......?......");

But not with QString i need to give on GenDateTime column where i am interested in retreiveing the records which 3 days less than current date and time. And also how do i get 3 days back date time from current date time.

Can anybody help me .......... Which will be very help ful..

Thank you
Babu