Issue with a button

Hi

 

I'd like to use a button to sort duplicates or no duplicates of names in a table.

So

I create a new field that I name "isDuplicate"

I create a button "isDuplicate" with the script :

 

let a := "" ;

for b in (select 'Feuille 1 OK-Tableau 1') order by 'Premier mot' do

if a = b. 'Premier mot' then

b.(isDuplicate := "Duplicate")

else

b.(isDuplicate := "Principal")

end ;

a := b.'Premier mot'

end

 

I get no error but when I click on the button nothing happens.

Could someone help le ?

Thank you