Two ways: First we can scan for correlations, and see the
list of values which can be correlated. From this we can
pick a value to be correlated. Secondly, we can record two
scripts and compare them. We can look up the difference file
to see for the values which needed to be correlated.  In my
project, there was a unique id developed for each customer,
it was nothing but Insurance Number, it was generated
automatically and it was sequential and this value was
unique. I had to correlate this value, in order to avoid
errors while running my script. I did using scan for
correlation.