Trouver la date manquante et l'ajouter au résultat - MySql

ce n'est peut-être pas une solution parfaite, mais cela pourrait vous donner le résultat :la deuxième requête après UNION ALL dans le SELECT interne doit renvoyer toutes les dates entre le MIN(created) et le MAX(created) de votre table avec la valeur du compteur 0.

    SELECT SUM(a.ctr)
      ,a.datecreated
  FROM 
  (

    SELECT COUNT(*) as ctr, date_format(created, '%d/%m/%y ') as datecreated 
    FROM mimesi_indexer.meta_served_clips
    GROUP BY DATE(created)
UNION ALL 
    select 0 as ctr, date_format(selected_date, '%d/%m/%y ') as datecreated 
       from 
     (select adddate('1970-01-01',t4.i*10000 + t3.i*1000 + t2.i*100 + t1.i*10 + t0.i) selected_date from
     (select 0 i union select 1 union select 2 union select 3 union select 4 union select 5 union select 6 union select 7 union select 8 union select 9) t0,
     (select 0 i union select 1 union select 2 union select 3 union select 4 union select 5 union select 6 union select 7 union select 8 union select 9) t1,
     (select 0 i union select 1 union select 2 union select 3 union select 4 union select 5 union select 6 union select 7 union select 8 union select 9) t2,
     (select 0 i union select 1 union select 2 union select 3 union select 4 union select 5 union select 6 union select 7 union select 8 union select 9) t3,
     (select 0 i union select 1 union select 2 union select 3 union select 4 union select 5 union select 6 union select 7 union select 8 union select 9) t4) v
    where selected_date 
    between (SELECT MIN(created) FROM mimesi_indexer.meta_served_clips)
        and (SELECT MAX(created) FROM mimesi_indexer.meta_served_clips)
   ) a
   group by a.datecreated
   order by month(a.datecreated), date(a.datecreated)