dynamic if statement

[upperdecksu at gmail.com]

I am new to python and struggling with creating a dynamic if statement. 

I have a set of queries that are run against various databases/tables.  The result is all the same in that I always get back the same field names.

What I want to do is total the results differently based on the table. so for instance

I query fld1, fld2, fld3, qty, qty2 from table1
then I loop thru the results 
  if fld1 = 'a' add qty to some_total1 

I query fld1, fld2, fld3, qty, qty2  from table2
then I loop thru the results 
  if fld2 = 'b' add qty to some_total1 

I query fld1, fld2, fld3, qty, qty2  from table3
then I loop thru the results 
  if fld3 = 'c' add qty2 to some_total1 

I created a database pair that contains (table1,fld1 = 'a',add qty to some_total1)
                                    (table2,fld2 = 'b',qty to some_total1)
                                    (table3,fld3 = 'c',qty2 to some_total1)

So I know which table I am using, I query my list pair but I cant see how to build the if statement using the results from the query. 

something like this would be the result 
var1 = "fld1 = 'a'"
result = "add qty to some_total1"

if var1:
  result