Amazon Redshift

Fully managed, petabyte-scale data warehouse for SQL analytics and BI reporting on large datasets.

Verified against AWS documentation · 2026-09-09

Key facts

  1. 01OLAP, not OLTP — built to scan and aggregate billions of rows, not to serve single-row app lookups
  2. 02Columnar storage + MPP: a leader node plans the query, compute nodes run it in parallel on their own slice of data
  3. 03Two flavours: Serverless (pay per RPU-second while active, no cluster to size) and Provisioned (node-hours, pause/resume, Reserved Instances)
  4. 04Spectrum queries data sitting in S3 directly — no loading, join warehouse tables to lake files in one SQL statement
  5. 05Reality check: AWS now steers new clusters to Graviton-based RG nodes with a built-in lake query engine; exam material still says RA3 and DC2

Exam triggers

Phrases and scenarios that point here.

  • "Data warehouse", "OLAP", "business intelligence", "petabyte-scale analytics", "complex joins across large tables"
  • Reporting queries are crushing the production database → move analytics to Redshift, leave RDS to the app
  • Analytics run only at month-end or business hours → Redshift Serverless, no capacity planning
  • Query existing S3 data from the warehouse without an ETL load → Redshift Spectrum

Not this service

  • Occasional ad hoc SQL over S3, nothing to run or manage → Athena
  • Transactional app database, single-row reads and writes → RDS or Aurora
  • Spark, Hadoop or custom processing instead of SQL → EMR
  • The dashboards and charts themselves → QuickSight (Redshift is what it queries)

Use cases

  1. 01One reporting warehouse fed nightly from orders, CRM and billing, so finance runs a single query instead of reconciling three exports
  2. 02Five years of clickstream in one place to answer questions no single app database can — which acquisition channel actually produces repeat buyers
  3. 03BI backend for QuickSight, Tableau or Power BI, where a few hundred analysts hit the same tables every Monday morning
  4. 04Hot months live in the warehouse, cold years stay in S3 as Parquet, and Spectrum joins both in one query — you keep the history without paying warehouse storage for it
  5. 05Serverless for a warehouse that only wakes up for the month-end close, so the other 25 days cost nothing in compute

How it's charged

  1. 01Two different meters: Provisioned bills per node-hour whether or not a query runs; Serverless bills RPU-hours per second, only while active, with a 60-second minimum
  2. 02Storage is billed separately as Redshift Managed Storage, per GB-month, independent of node count — so you scale data without adding nodes
  3. 03Spectrum is $5 per TB scanned from S3 (10 MB minimum per query); compressing and using Parquet cuts the bill by orders of magnitude. Serverless and RG include lake queries with no separate Spectrum charge
  4. 04Concurrency Scaling: one free hour of credits earned per 24 hours of cluster uptime, accruing up to 30 hours — enough for most workloads before the per-second rate kicks in
  5. 05Reserved Instances (1 or 3 year) discount steady provisioned clusters; Serverless Reservations save up to 45% on a 3-year term. Pausing a cluster stops compute billing but you still pay for snapshots

Commonly confused with

References