MYSQL QUERY ersetzt NULL-Wert in einer Zeile durch Durchschnittswerte

Ich gebe zu, nicht die eleganteste, aber es sollte Ihnen das bringen, was Sie wollen.

Ich bin mir nicht sicher, wie Sie mit diesen NULL-Werten umgehen möchten, die einen Stundendurchschnitt von NULL haben. Im Beispiel unten werden diese auf -1 aktualisiert.

create table myTable
(myDate datetime not null,
P_f decimal(10,5) default null
);

insert into myTable(myDate,P_f) values ('2001-01-01 20:20:00',1.88);
insert into myTable(myDate,P_f) values ('2001-01-01 20:25:00',NULL);
insert into myTable(myDate,P_f) values ('2001-01-01 20:30:00',NULL);
insert into myTable(myDate,P_f) values ('2001-01-01 20:35:00',1.71);
insert into myTable(myDate,P_f) values ('2001-01-01 20:40:00',NULL);
insert into myTable(myDate,P_f) values ('2001-01-01 20:45:00',NULL);
insert into myTable(myDate,P_f) values ('2001-01-01 20:50:00',NULL);
insert into myTable(myDate,P_f) values ('2001-01-01 20:55:00',1.835);
insert into myTable(myDate,P_f) values ('2001-01-01 21:00:00',1.918);
insert into myTable(myDate,P_f) values ('2001-01-01 21:05:00',1.968);
insert into myTable(myDate,P_f) values ('2001-01-01 21:10:00',2.004);
insert into myTable(myDate,P_f) values ('2001-01-01 21:15:00',1.924);
insert into myTable(myDate,P_f) values ('2001-01-01 21:20:00',1.8625);
insert into myTable(myDate,P_f) values ('2001-01-01 21:25:00',1.94);
insert into myTable(myDate,P_f) values ('2001-01-01 21:30:00',2.0375);
insert into myTable(myDate,P_f) values ('2001-01-01 21:35:00',1.912);
insert into myTable(myDate,P_f) values ('2001-01-02 20:40:00',NULL);

-- Insert copy of null value P_f rows into myTable with 1 hour average about myDate 
insert into myTable
(myDate,P_f)
select t.myDate,ifnull((select avg(P_f) from myTable t1 where t1.myDate between t.myDate - interval 1 hour and t.myDate +interval 1 hour),-1) as hourAvg
from myTable t
where t.P_f is null;

-- delete rows where P_f is null
delete from myTable
where P_f is null;