cursor_current

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.

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

['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 5

['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 5

List of related functions

• ingestion_time: Use ingestion_time to get the time when data was ingested. Use cursor_current for resumable query execution tracking.
• now: Use now to get the current query execution time. Use cursor_current for position tracking in data streams.
• bin: Use bin to group data into time buckets. Use cursor_current alongside bin for checkpointed time-series processing.

Other query languages