Stacked area chart

I had this problem and used the following workaround:

If source data is derived for example from:

       SELECT

              AAA,                        -- The Legend

              A_DATE,                   -- Time series

              A_VALUE                  -- Stacked value

       FROM TABLE_A;

Then replacing it with the following resolved the problem for me:

       SELECT

              AAA,

              A_DATE,

              A_VALUE

       FROM TABLE_A

       UNION ALL

       SELECT DISTINCT

              AAA,

              cj.A_DATE,

              0 AS A_VALUE

       FROM TABLE_A

       CROSS JOIN ( SELECT DISTINCT A_DATE FROM TABLE_A ) cj  ;

My problem was actually as described by dedelman_clng (new legend starts mid series), but I think it should work for scattered nulls also.