analytics-ruby

name	analytics-ruby
summary	Couchbase Analytics Service (CBAS) for Ruby — run OLAP queries, window functions, and external data links without impacting operational workloads (Server 6.x–7.x; use columnar-analytics for Server 8+)
description	Couchbase Analytics Service (CBAS) for Ruby — run OLAP queries, window functions, and external data links without impacting operational workloads (Server 6.x–7.x; use columnar-analytics for Server 8+)
compatibility	Ruby SDK 3.x. Requires couchbase>=3.0.
metadata	{"last_verified":"2026-05","min_server_version":"6.0","deprecated_by":"columnar-analytics","deprecated_since":"8.0","max_server_version":"7.6","handoff":[{"condition":"user asks about SQL++ queries","skill":"server-querying-ruby"},{"condition":"user is upgrading to Server 8.x and wants the columnar engine","skill":"columnar-analytics"}]}

Couchbase Analytics — Ruby

Version disambiguation: This skill covers Couchbase Server 6.x–7.x (legacy CBAS). If the user mentions Server 8, Couchbase 8, or the columnar engine, route to columnar-analytics instead. If the server version is unknown, ask before proceeding. Analytics runs OLAP queries on a shadow copy of your data, isolated from KV and Query Service workloads. Use it for aggregations, reports, and joins across large datasets.

---

Setup — Create an Analytics Collection

-- Link the default bucket (once, in the Analytics workbench or cbsh)
CREATE DATAVERSE myapp IF NOT EXISTS;
USE myapp;
CREATE ANALYTICS COLLECTION orders ON `myapp`.`_default`.`orders` IF NOT EXISTS;

---

Running Analytics Queries

The Ruby SDK uses cluster.analytics_query().

require 'couchbase'

cluster = Couchbase::Cluster.connect(
  'couchbase://localhost',
  Couchbase::Options::Cluster.new(
    authenticator: Couchbase::PasswordAuthenticator.new(
      ENV['CB_USERNAME'], ENV['CB_PASSWORD']
    )
  )
)

# Simple aggregation
result = cluster.analytics_query(
  'SELECT country, COUNT(*) AS cnt FROM orders GROUP BY country ORDER BY cnt DESC'
)
result.rows.each { |row| puts row }

Parameterized queries

result = cluster.analytics_query(
  'SELECT * FROM orders WHERE country = $country',
  Couchbase::Options::Analytics.new(
    named_parameters: { country: 'US' }
  )
)

Window functions

result = cluster.analytics_query(<<~SQL)
  SELECT name, country, stars,
         RANK() OVER (PARTITION BY country ORDER BY stars DESC) AS rank
  FROM hotels
SQL

---

Key differences from operational SQL++

	Analytics (analytics_query)	Operational (query)
Data source	Shadow copy (async replicated)	Live data
Isolation	No impact on KV/Query	Shares Query Service resources
Consistency	Eventually consistent	Configurable (request_plus)
Use case	OLAP, reports, large joins	OLTP, low-latency lookups

Analytics vs Query Service: See shared/server/analytics-vs-query.md for the full comparison, setup steps, and common errors.

---

Writing Results Back

Ruby SDK 3.x does not support distributed ACID transactions, so there is no transactional write-back path from analytics results to the operational store.

To write analytics results back, use individual KV upsert operations:

result = cluster.analytics_query('SELECT id, total FROM orders WHERE status = "complete"')
collection = cluster.bucket('myapp').default_collection

result.rows.each do |row|
  collection.upsert("summary::#{row['id']}", { total: row['total'], synced_at: Time.now.iso8601 })
end

For concurrent writes, see sdk-patterns-ruby for bulk upsert patterns.

Troubleshooting

Error	Cause	Fix
DataverseNotFoundException	Analytics collection not created	Run CREATE ANALYTICS COLLECTION
CompilationException	SQL++ syntax error	Check field names and dataverse
Slow query	Missing index or large dataset	Add Analytics index or filter earlier