Vensterfuncties gebruiken in een update-instructie

De fout is van postgres, niet van django. Je kunt dit herschrijven als:

WITH v_table_name AS
(
    SELECT row_number() over (partition by col2 order by col3) AS rn, primary_key
    FROM table_name
) 
UPDATE table_name set table_name.col1 = v_table_name.rn
FROM v_table_name
WHERE table_name.primary_key = v_table_name.primary_key;  

Of anders:

UPDATE table_name set table_name.col1 = v_table_name.rn
FROM  
(
    SELECT row_number() over (partition by col2 order by col3) AS rn, primary_key
    FROM table_name
) AS v_table_name
WHERE table_name.primary_key = v_table_name.primary_key;

Dit werkt. Net getest op postgres-9.6. Hier is de syntaxis voor UPDATE (zie de optionele fromlist ).

Ik hoop dat dit helpt.