Ist es das was du meinst?
drop table if exists tbl;
create table tbl(
timestamp timestamp,
device varchar(32),
type varchar(8),
event varchar(64),
reading varchar(32),
value decimal(8,4),
unit varchar(8)
);
insert into tbl values
('2020-11-13 19:26:02', 'DatabaseLog', 'DBLOG', 'CacheUsage: 2' , 'CacheUsage' , 2 , ''),
('2020-11-13 19:26:02', 'DatabaseLog', 'DBLOG', 'background_processing_time: 0.0152', 'background_processing_time', 0.0152, ''),
('2020-11-13 19:26:02', 'DatabaseLog', 'DBLOG', 'sql_processing_time: 0.0042' , 'sql_processing_time' , 0.0042, ''),
('2020-11-13 19:26:02', 'DbLog' , 'DBLOG', 'CacheUsage: 145' , 'CacheUsage' , 145 , '');
-- DELETE
delete a
from tbl a
join tbl b using(timestamp,reading)
where a.device='DatabaseLog' and b.device='DbLog';
select * from tbl;
+---------------------+-------------+-------+------------------------------------+----------------------------+----------+------+
| timestamp | device | type | event | reading | value | unit |
+---------------------+-------------+-------+------------------------------------+----------------------------+----------+------+
| 2020-11-13 19:26:02 | DatabaseLog | DBLOG | background_processing_time: 0.0152 | background_processing_time | 0.0152 | |
| 2020-11-13 19:26:02 | DatabaseLog | DBLOG | sql_processing_time: 0.0042 | sql_processing_time | 0.0042 | |
| 2020-11-13 19:26:02 | DbLog | DBLOG | CacheUsage: 145 | CacheUsage | 145.0000 | |
+---------------------+-------------+-------+------------------------------------+----------------------------+----------+------+