Use the cursor_current function in APL to retrieve a cursor string that represents the current point in the query execution. A cursor is a unique identifier that marks a specific position in your data stream, allowing you to resume queries from that exact point in subsequent executions.
You use cursor_current when implementing incremental data processing, change data capture (CDC) patterns, or any scenario where you need to track the last processed position in your data. This is particularly useful for building efficient data synchronization pipelines, continuous monitoring systems, and incremental analytics workflows.
For users of other query languages
If you come from other query languages, this section explains how to adjust your existing queries to achieve the same results in APL.
In Splunk SPL, you typically use time-based bookmarks or the _indextime field to track processing positions. APL's cursor_current provides a more robust cursor mechanism that works across query executions and handles distributed data more reliably.
['sample-http-logs']
| extend cursor = cursor_current()
| summarize max(_time), last_cursor = make_list(cursor)[0]In ANSI SQL, you typically use MAX(timestamp) or row IDs to track the last processed record. APL's cursor_current provides a system-level cursor that captures the exact query execution position, which is more reliable for distributed systems.
['sample-http-logs']
| extend cursor = cursor_current()
| summarize max(_time), processing_cursor = make_list(cursor)[0]Usage
Syntax
cursor_current()Parameters
This function takes no parameters.
Returns
A string representing a cursor that marks the current position in the query execution. This cursor can be stored and used in subsequent queries to resume processing from the same point.
Use case examples
Use cursor_current to track the last processed position when implementing incremental log processing pipelines.
Query
['sample-http-logs']
| extend processing_cursor = cursor_current()
| where status != '200'
| summarize error_count = count(), last_cursor = make_list(processing_cursor)[0] by bin(_time, 5m)
| take 5Output
| error_count | last_cursor |
|---|---|
| 343,769 | 0ddnv2035n4lc-082f23975a003f6b-00006d10 |
This query captures cursor positions alongside error counts, allowing you to resume processing from the last successful position in case of failures or for incremental updates.
Use cursor_current to implement incremental trace processing for building derived metrics or alerts based on span data.
Query
['otel-demo-traces']
| extend trace_cursor = cursor_current()
| where kind == 'server'
| summarize span_count = count(), latest_cursor = make_list(trace_cursor)[0] by ['service.name'], bin(_time, 5m)
| take 5Output
| ['service.name'] | span_count | latest_cursor |
|---|---|---|
| frontend | 234 | cur_xyz456abc789 |
| cart | 187 | cur_mno123pqr456 |
This query tracks the processing position for each service, enabling resumable trace analysis and incremental metric computation.
List of related functions
- ingestion_time: Use
ingestion_timeto get the time when data was ingested. Usecursor_currentfor resumable query execution tracking. - now: Use
nowto get the current query execution time. Usecursor_currentfor position tracking in data streams. - bin: Use
binto group data into time buckets. Usecursor_currentalongsidebinfor checkpointed time-series processing.