Specifying cycle count with one equity operator

If one end of the time range is excluded (by using > instead of >= or < instead of <=). then a gap of "resolution" is left at the beginning (or end) of the result set.

The resolution is calculated as (end date – start date) / (cyclecount).

The row that equates to the time which is designated using the < (or >) operator is not returned.

These queries use the remote table view.

Query 1

This query uses a cycle count of 60, resulting in a 1 second resolution for the data. The starting time is set to >=.

SELECT DateTime, Value

FROM History

WHERE TagName = 'SysTimeSec'

AND wwCycleCount = 60

AND DateTime >= '2001-01-13 12:00:00'

AND DateTime < '2001-01-13 12:01:00'

The results are:

(60 row(s) affected)

Query 2

This query also uses a cycle count of 60, resulting in a 1 second resolution for the data. The ending time is set to <=.

SELECT DateTime, Value

FROM History

WHERE TagName = 'SysTimeSec'

AND wwCycleCount = 60

AND DateTime > '2001-01-13 12:00:00'

AND DateTime <= '2001-01-13 12:01:00'

The results are:

(60 row(s) affected)