Trigger.AvailableNow()

In the Ultra Transcenders books

DBX-DEP

Each book explains Trigger.AvailableNow() in context, with comparison tables and the common traps.

Terms in this definition

• Structured Streaming trigger

  Configured on the writer of a Spark streaming query, it governs when data gets processed and whether the query keeps going. Options: processing time, running microbatches one after another either straight away or every set interval; available now, which works through existing data then ends; and, from Runtime 2.0, low-latency Real-time Mode.

• ALL

  A DAX function that ignores any filters and gives back every row of a table or every value of the named columns. Used within CALCULATE, it works as a modifier that clears filters, although REMOVEFILTERS states that intent more clearly where it is available.

• Serverless

  Compute tier for single Azure SQL databases that scales automatically, pauses when idle and charges by the second. It is offered in General Purpose and Hyperscale, not Business Critical, and reserved capacity does not apply.

Related terms

• Asynchronous progress tracking

  Keeps processing moving in Structured Streaming while offset and commit log writes happen asynchronously. A query fails if it combines this with an AvailableNow or Once trigger.

• Incremental batch

  An approach that runs Structured Streaming with the availableNow trigger: it picks up only records added since the previous run and then shuts down, giving scheduled jobs streaming-style progress tracking for the cost of a batch.

• Streaming trigger

  Controls how often a Structured Streaming query checks for new data, through options such as processingTime and availableNow. That choice trades latency against cost.