Example 2: delta and full retrieval
- Last UpdatedMar 19, 2025
- 2 minute read
In delta and full mode, the wwResolution column is used in the query results to show the time in milliseconds until the next point. When the first point in the result occurs before the query start time, the wwResolution column shows the time from the start of the query to the next point. If there are no more points after the first point, the wwResolution column is NULL.
For example, the following data is stored:
|
DateTime |
Value |
|---|---|
|
2012-01-01 07:59:53 |
34.42384 |
If you query for the data between 2012-01-01 08:00:00 to 2012-01-01 08:00:10, the results are:
|
DateTime |
Value |
wwResolution |
|---|---|---|
|
2012-01-01 08:00:00 |
34.42384 |
NULL |
However, if the data stored is:
|
DateTime |
Value |
|---|---|
|
2012-01-01 07:59:53 |
34.42384 |
|
2012-01-01 08:00:13 |
15.02637 |
Then the results are:
|
DateTime |
Value |
wwResolution |
|---|---|---|
|
2012-01-01 08:00:00 |
34.42384 |
10000 |
When the last point in the result occurs before the query end time, the wwResolution column shows the time until the end of the query when there is a next available point. If there are no more points, then the wwResolution column shows NULL.
For example, the following is stored:
|
DateTime |
Value |
|---|---|
|
2012-01-01 07:59:53 |
34.42384 |
|
2012-01-01 08:00:13 |
15.02637 |
|
2012-01-01 08:00:33 |
20.29732 |
|
2012-01-01 08:00:53 |
37.40273 |
|
2012-01-01 08:01:13 |
24.31662 |
If you query for data from 2012-01-01 08:00:00 to 2012-01-01 08:05:00, the results are:
|
DateTime |
Value |
wwResolution |
|---|---|---|
|
2012-01-01 08:00:00 |
34.42384 |
13000 |
|
2012-01-01 08:00:13 |
15.02637 |
20000 |
|
2012-01-01 08:00:33 |
20.29732 |
20000 |
|
2012-01-01 08:00:53 |
37.40273 |
20000 |
|
2012-01-01 08:01:13 |
24.31662 |
NULL |
If you query for data from 2012-01-01 08:00:00 to 2012-01-01 08:01:00, the results are:
|
DateTime |
Value |
wwResolution |
|---|---|---|
|
2012-01-01 08:00:00 |
34.42384 |
13000 |
|
2012-01-01 08:00:13 |
15.02637 |
20000 |
|
2012-01-01 08:00:33 |
20.29732 |
20000 |
|
2012-01-01 08:00:53 |
37.40273 |
7000 |
If the last point happens to be end of the query, then the wwResolution value is zero, even when there are no more points after the last point. For example, if you query for data from 2012-01-01 08:00:00 to 2012-01-01 08:01:13, the results are:
|
DateTime |
Value |
wwResolution |
|---|---|---|
|
2012-01-01 08:00:00 |
34.42384 |
13000 |
|
2012-01-01 08:00:13 |
15.02637 |
20000 |
|
2012-01-01 08:00:33 |
20.29732 |
20000 |
|
2012-01-01 08:00:53 |
37.40273 |
20000 |
|
2012-01-01 08:01:13 |
24.31662 |
0 |