T-SQL在最后一分钟对至少具有一个位置的IsGood等于true的所有车辆进行计数

Question

I have a table called VehiclePosition that contains a big amount of data that is increasing aprox every second.

The structure of this table is something like:

VId       | TimestampLocal                     | IsGood
----------+------------------------------------+--------
20        | 2017-08-25 13:17:13.6000000 -04:00 | 1
20        | 2017-08-25 13:17:14.2000000 -04:00 | 1
20        | 2017-08-25 13:17:19.8000000 -04:00 | 0
21        | 2017-08-25 13:17:58.6000000 -04:00 | 0
21        | 2017-08-25 13:18:00.1000000 -04:00 | 0

The query should return just VehicleId 20 because in the last minute (13:17 - 13.18) only this vehicle had at least one position with IsGood = 1.

My query

select p.VId 
from VehiclePosition p 
where p.VId = (select distinct VId 
               from VehiclePosition 
               where TimestampLocal > GETDATE() 
                     and IsGood = 0)

but it seems that loads very slow and returns

Subquery returned more than 1 value. This is not permitted when the subquery follows =, !=, <, <= , >, >= or when the subquery is used as an expression. and I don't know what am I doing wrong.

I'm new in T-SQL queries, so please be gentle :)

Answer 1

The marker for a vehicle which should appear in your result is that within one minute of the greatest timestamp value in your table that vehicle appeared at least once in good condition. If so, you can try the following query:

SELECT DISTINCT
    p.VId
FROM VehiclePosition p
WHERE
    IsGood = 1 AND
    TimestampLocal >= DATEADD(minute, -1, GETDATE())

I used SELECT DISTINCT here because we only want to report each vehicle once. That is, if a vehicle appeared in the last minute in good condition twice, we would only want to list it once.

Answer 2

select * from VehiclePosition P 
    where abs(datediff(minute, P.timestamp_local, getdate())) <= 1 and is_good = 1

Result (with the current date = '2017-08-25 13:18' ):

id  timestamp_local         is_good
--- ----------------------- -------
20  2017-08-25 13:17:13.000 1
20  2017-08-25 13:17:14.000 1

Rextester Demo.