Cyclic retrieval - query example
- Last UpdatedFeb 05, 2025
- 1 minute read
To use the cyclic retrieval mode, set the following parameter in your query.
wwRetrievalMode = 'Cyclic'
For example, the following query returns data values for the analog tag 'ReactLevel'. If you do not specify a wwCycleCount or wwResolution, the query will return 100 rows (the default).
SELECT DateTime, Sec = DATEPART(ss, DateTime), TagName, Value
FROM History
WHERE TagName = 'ReactLevel'
AND DateTime >= '2001-03-13 1:15:00pm'
AND DateTime <= '2001-03-13 2:15:00pm'
AND wwRetrievalMode = 'Cyclic'
The results are:
|
DateTime |
Sec |
TagName |
Value |
|
2001-03-13 13:15:00.000 |
0 |
ReactLevel |
1775.0 |
|
2001-03-13 13:15:00.000 |
36 |
ReactLevel |
1260.0 |
|
2001-03-13 13:16:00.000 |
12 |
ReactLevel |
1650.0 |
|
2001-03-13 13:16:00.000 |
49 |
ReactLevel |
1280.0 |
|
2001-03-13 13:17:00.000 |
25 |
ReactLevel |
1525.0 |
|
2001-03-13 13:18:00.000 |
1 |
ReactLevel |
585.0 |
|
2001-03-13 13:18:00.000 |
38 |
ReactLevel |
1400.0 |
|
2001-03-13 13:19:00.000 |
14 |
ReactLevel |
650.0 |
|
2001-03-13 13:19:00.000 |
50 |
ReactLevel |
2025.0 |
|
2001-03-13 13:20:00.000 |
27 |
ReactLevel |
765.0 |
|
2001-03-13 13:21:00.000 |
3 |
ReactLevel |
2000.0 |
|
2001-03-13 13:21:00.000 |
39 |
ReactLevel |
830.0 |
|
2001-03-13 13:22:00.000 |
16 |
ReactLevel |
1925.0 |
|
... |
|||
|
(100 row(s) affected) |