SELECT
IIF(MAXVALUE(COALESCE(P.DH_INCLUSAO, CURRENT_TIMESTAMP), COALESCE(G.DH_ALTERACAO, CURRENT_TIMESTAMP), COALESCE(FG.DH_ALTERACAO, CURRENT_TIMESTAMP)) >= '01/01/2020', 'I',
    IIF(MAXVALUE(COALESCE(P.DH_INCLUSAO, CURRENT_TIMESTAMP), COALESCE(G.DH_ALTERACAO, CURRENT_TIMESTAMP), COALESCE(FG.DH_ALTERACAO, CURRENT_TIMESTAMP)) <= '01/01/2020' AND
        MAXVALUE(COALESCE(P.DH_ALTERACAO, CURRENT_TIMESTAMP), COALESCE(G.DH_ALTERACAO, CURRENT_TIMESTAMP), COALESCE(FG.DH_ALTERACAO, CURRENT_TIMESTAMP)) >= '01/01/2020', 'A', '')) ACAO
  FROM PRODUTO P
 INNER JOIN GRUPO G
    ON G.COD_GRUPO = P.COD_GRUPO
 INNER JOIN FUNCIONARIO_GRUPO FG
    ON FG.COD_GRUPO = G.COD_GRUPO