Power table column data search separate DB table for match

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3

I would build a dictionary with the vendor keys before loading the CSV.
Then you can just do a has_key check in the dictionary for each read line in the CSV.
Then add the result to the dataset.

existsDic = {}
vDS = system.db.runQuery('Select VendorID,VendorName FROM tblVendors','MyDatabaseConn')
existsDic = dict(svr)

for line in d.readlines():
    if existsDic.has_key(line[0]):
        #DoSomething for existing Vendor
    else:
        #Do something for new Vendor

Something along those lines