结合两个复杂的SQL查询

Question

So I've arrived at the absolute limit of my sql prowess and I can't for the life of me combine these two queries, First off here's what my database looks like

Current - Table

ID - Unique identifier for device (Int)  
Location -Unique identifier for name of area (VarChar)  
Status - The current status of the device (VarChar )  
Time - DateTime of when the last connection was made to the device (DateTime)

Historical

CID (Sorta unused, just as an AI field to store multiple old bits of data uniquely) (Int)  
ID - Unique identifier for device (Int)  
Location --Unique identifier for name of area (VarChar)  
Status - The current status of the device (VarChar )  
Time -- DateTime of when the last connection was made to the device (DateTime)

So with that all said here's the two queries:

Query 1:

SELECT *, if(HOUR(TIMEDIFF(NOW(), TIME)) >=1, 1, 0) as OlderThanAnHour
FROM Current
WHERE Location like "MyLocation"

Query 2:

SELECT ID, min(time), (abs(timestampdiff(HOUR,NOW(),TIME))/count(*)*100) as percentage
from Historical
where LOCATION like "MyLocation"
group by ID

My goal is to combine them into a single query, since it's going to be called often

Answer 1

Try:

SELECT c.*, 
       if(HOUR(TIMEDIFF(NOW(), c.TIME)) >=1, 1, 0) as LatestOlderThanAnHour,
       min(h.time) as EarliestTime, 
       (abs(timestampdiff(HOUR,NOW(),min(TIME)))/count(*)*100) as percentage
FROM Current c
JOIN Historical h on c.ID = h.ID
WHERE c.Location like "MyLocation"
group by c.ID