How can I take the ids of the registrations with the highest temperature of each day (on a specified period of time)?

Question

Considering I have more than 30 registers/day for that temperature.

• Name of the table: 'temperatures'
• Colomn name: 'TempA'

I want one registration for each day, for example:

date: 2015-12-10 12:02 id: 2341 tempa: 54 (which is the highest on that day)
date: 2015-12-09 15:04 id 1923 tempa: 32 (which is the highest on that day)

and so on....

Answer 1

您可以使用max和group by

select max(TempA) from your_table group by day_column

Answer 2

select id from temperatures where TempA=(select max(TempA) from temperatures )