preview plugin
Applies to: ✅ Azure Data Explorer
Returns a table with up to the specified number of rows from the input record set, and the total number of records in the input record set.
Syntax
T | evaluate preview(NumberOfRows)
Learn more about syntax conventions.
Parameters
| Name | Type | Required | Description |
|---|---|---|---|
| T | string |
✔️ | The table to preview. |
| NumberOfRows | int |
✔️ | The number of rows to preview from the table. |
Returns
The preview plugin returns two result tables:
- A table with up to the specified number of rows.
For example, the sample query above is equivalent to running
T | take 50. - A table with a single row/column, holding the number of records in the
input record set.
For example, the sample query above is equivalent to running
T | count.
Note
- Using additional operators after the
previewplugin results in a query failure. Thepreviewplugin should be the last operator of the query because it returns two result tables.
Example
StormEvents | evaluate preview(5)
Table1
The following output table only includes the first 6 columns. To see the full result, run the query.
| StartTime | EndTime | EpisodeId | EventId | State | EventType | ... |
|---|---|---|---|---|---|---|
| 2007-12-30T16:00:00Z | 2007-12-30T16:05:00Z | 11749 | 64588 | GEORGIA | Thunderstorm Wind | ... |
| 2007-12-20T07:50:00Z | 2007-12-20T07:53:00Z | 12554 | 68796 | MISSISSIPPI | Thunderstorm Wind | ... |
| 2007-09-29T08:11:00Z | 2007-09-29T08:11:00Z | 11091 | 61032 | ATLANTIC SOUTH | Waterspout | ... |
| 2007-09-20T21:57:00Z | 2007-09-20T22:05:00Z | 11078 | 60913 | FLORIDA | Tornado | ... |
| 2007-09-18T20:00:00Z | 2007-09-19T18:00:00Z | 11074 | 60904 | FLORIDA | Heavy Rain | ... |
Table2
| Count |
|---|
| 59066 |