State-of-the-World

📄️What is the difference between a Topic in the SOW and the Transaction Log?

Learn the critical differences between AMPS State of the World Topics and the Transaction Log for managing message state and replayability.

📄️How does a messaging product support queries?

Learn how AMPS messaging products support high-performance queries against real-time data stored in a State of the World (SOW) database.

📄️How do I subscribe to a view or an aggregate in my program?

Learn how to subscribe to views or aggregates in AMPS using standard topic subscription methods in your program.

📄️How can I paginate a SOW Query?

Learn how to easily paginate SOW queries in AMPS using the skip_n, top_n, and OrderBy options for result set management.

📄️What happens if data changes while a SOW query is running?

AMPS guarantees SOW query atomicity, snapshotting data at the start time, or use `sow_and_subscribe` for ongoing updates.

📄️Does AMPS return messages from the SOW in the order published?

AMPS does not guarantee SOW message order; use timestamps or OrderBy parameters for ordered retrieval.

📄️How many columns/fields can I have in a SOW topic? In a view?

AMPS has no practical limit on the number of fields in a SOW topic or view, though large message sizes impact performance.

📄️What is "Focus" in AMPS?

Learn about AMPS "Focus" and "Out of Focus" (OOF) notifications for message subscription updates.

📄️What are some ways to consume large SOW queries?

Learn how to manage large SOW queries in AMPS using pagination and fine-tuning slow consumer mitigation settings.

📄️Do I need to list every field in a SOW topic configuration?

SOW topic configuration only requires listing Key fields, not every field in a message for proper identification.

📄️How can I get the number of records in a SOW topic?

Learn the best methods for efficiently getting the record count in an AMPS SOW topic without transferring all data.

📄️How can I delete messages from a SOW topic?

Learn the four primary methods for deleting messages from an AMPS SOW topic, including timed expiration and command-line cleanup.

📄️Should I use the SOW delete action or message expiration to maintain my SOW?

Choose between SOW delete action or message expiration based on your application's data lifecycle and workflow needs.

📄️How do I configure SOW storage parameters?

Learn how to configure SOW storage parameters like SlabSize to manage growth and support larger messages in your application.

📄️How do I only get the first 100 records from a SOW Query?

Learn how to limit SOW query results to the top 100 records using the `top_n` option in AMPS.

📄️What is the difference between historical SOW and bookmark replay?

Clarifies the key differences between historical SOW queries (snapshots) and bookmark replays (message stream playback).

📄️Do I have to add configuration for every topic I want to publish to?

AMPS does not require topic configuration for basic publish/subscribe, only for message persistence features.

📄️How does AMPS construct the SowKey for a message?

Learn how AMPS constructs the SowKey for a message using topic key fields and the KeyDomain via CRC checksum.

📄️What happens if I change the key of a SOW topic?

Learn the risks and necessary steps when changing SOW topic keys in AMPS configuration.