-- INIT database

CREATE TABLE devicelog (

  id int,

  yourdatecolumn date,

  devicetype VARCHAR2(255)

);

​

insert into devicelog values (1,sysdate,'thing');

​

insert into devicelog values (1,sysdate,'thing');

​

insert into devicelog values (1,sysdate-2,'thing');

​

insert into devicelog values (2,sysdate,'thing 2');

​

​

insert into devicelog values (3,sysdate,'thing 3');

​

insert into devicelog values (3,sysdate,'thing 3');

​

insert into devicelog values (3,sysdate-3,'thing 3');

​

select * from (

select id,yourdatecolumn,devicetype, row_number() over(partition by id, yourdatecolumn order by yourdatecolumn asc) as rn

from devicelog 

  ) foo 

where rn=1;