# Fresh context: change data capture, not batch ETL

DevFeed: [Fresh context: change data capture, not batch ETL](<https://devfeed.tech/articles/fresh-context-change-data-capture-not-batch-etl-4773.md>)

Original publisher: [Read original article](<https://redis.io/blog/change-data-capture-vs-batch-etl-ai-agents/>)

Author: Simran Regmi

Published: 2026-08-12T00:00:00Z

Content type: tutorial

Language: en

Sources: [Redis Blog](<https://devfeed.tech/sources/redis-blog.md>)

Topics: [event driven](<https://devfeed.tech/topics/event-driven.md>), [data](<https://devfeed.tech/topics/data.md>), [Database](<https://devfeed.tech/topics/database.md>), [PostgreSQL](<https://devfeed.tech/topics/postgresql.md>)

Tags: [agent](<https://devfeed.tech/tags/agent.md>), [applications](<https://devfeed.tech/tags/applications.md>), [batch](<https://devfeed.tech/tags/batch.md>), [canada](<https://devfeed.tech/tags/canada.md>), [customer](<https://devfeed.tech/tags/customer.md>), [data](<https://devfeed.tech/tags/data.md>), [database](<https://devfeed.tech/tags/database.md>), [event](<https://devfeed.tech/tags/event.md>), [event-driven](<https://devfeed.tech/tags/event-driven.md>), [events](<https://devfeed.tech/tags/events.md>), [guide](<https://devfeed.tech/tags/guide.md>), [postgresql](<https://devfeed.tech/tags/postgresql.md>), [systems](<https://devfeed.tech/tags/systems.md>), [tech-de](<https://devfeed.tech/tags/tech-de.md>)

## AI overview

This guide explains how change data capture (CDC) keeps agent context current by forwarding database inserts, updates, and deletes as events. It contrasts CDC with nightly batch ETL, which can leave agents using stale policies or pricing, and describes log-based, trigger-based, and polling approaches.

## Source excerpt

In many systems, the reason an agent quotes yesterday's data isn't the model. It's the pipeline behind it: a nightly ETL job that refreshed the agent's context hours ago. Change data capture (CDC) can shrink that staleness window from hours to seconds...