Amazon Redshift

Concepts

Query directly from source

Zenskar can connect to a data source by syncing it into Zenskar, or by querying it live. With Directly from source, no data is copied into Zenskar. Each time a billable metric runs, Zenskar sends the SQL straight to your Redshift cluster or workgroup and returns the live result. This means no sync lag and no duplicate copy of your data, but it also means Redshift must be reachable from Zenskar’s servers for every query, not just during initial setup.

Why network access matters

Since queries run live, Zenskar’s servers need an open path to your cluster or workgroup on every request. That is why the endpoint must be reachable (publicly, or via private networking), and why the VPC security group must allow inbound traffic from Zenskar’s IP address on port 5439. If this path is missing, a connection typically hangs and times out rather than failing with a clear error, so it is worth confirming before setup.

How SSL fits in

Redshift presents a trusted certificate by default, so encryption works out of the box with SSL mode and certificate fields left blank. Full certificate verification (verify-ca or verify-full) is an extra layer for organizations whose security policy requires it, not a replacement for the default encryption, and most setups do not need it.

How billable metrics use a remote data source

A metric’s SQL builder can pull from synced data or remote data. Choosing Remote data and a Redshift source created with Directly from source is what lets the metric query Redshift each time it runs. Zenskar variables, such as customer external ID and billing start and end dates, are placeholders substituted at run time, so one query can serve every customer and billing period instead of needing a separate query for each.

How-to guides

How to add Amazon Redshift as a data source

Before you begin, gather your connection details and confirm your Redshift endpoint is reachable from Zenskar’s servers. You can find the endpoint in the AWS console, under Amazon Redshift > your cluster or Redshift Serverless > Workgroup configuration > General information. Copy only the endpoint host, the part before :5439/dev.

Open the data sources page

From the left navigation, go to Data sources, then click Add new data source in the top right.

Select Amazon Redshift

In the source type list, choose Amazon Redshift.

Choose direct access

Under Source access, select Directly from source. This is the option that lets a billable metric query Redshift live, without syncing data into Zenskar.

Enter the connection details

Fill in the connection fields using the values you gathered: host, port, database name, username, schema, and password.

Type the password raw, without URL-encoding it. Zenskar handles any encoding internally.

Configure SSL

Leave SSL connection enabled. For a standard setup, leave SSL mode and the certificate fields blank. Only set SSL mode to verify-ca or verify-full, and paste your Amazon Redshift CA certificate, if your security policy requires full certificate verification. Client certificate and client key fields are not used by Redshift and should stay blank.

Save

Click Save. The new data source appears in your list with status Active and is immediately ready to query.

Connection and SSL reference

Look up every connection field, network access requirement, and SSL option.

How to query Redshift from a billable metric

Open the SQL builder

Go to Usage > Billable metrics, create a new metric or open an existing one, then switch to the SQL builder tab.

Set the source to remote data

Under Source of data, select Remote data instead of Synced data. From the Remote datasource dropdown, choose the Amazon Redshift source you created earlier.

If the dropdown is empty, the source was not created with Directly from source access. Go back and check the previous how-to guide.

Browse your tables

Use the Data Navigator panel to browse the tables Zenskar can see in your Redshift database. Click a table to insert its name into the query editor.

Write your query

Write standard SQL against your Redshift tables. Use the Zenskar Variables tab to insert billing context values, such as Customer External ID, Billing Start Date, and Billing End Date, that Zenskar fills in at run time.

SELECT NULLIF(COUNT("transaction_id"), 0) AS "quantity"
FROM transactions
WHERE DATE("timestamp") >= DATE( {Billing Start Date} )
  AND DATE("timestamp") <= DATE( {Billing End Date} )
  AND "customer_id" = CAST( {Customer External ID} AS VARCHAR )
  AND "transaction_status" = true

Preview the result

In the Query preview bar, pick a customer and a billing period, then click Run query to see the rows Zenskar returns from Redshift.

Make sure your test data falls inside the chosen billing period, or the result will be empty.

Save the metric

When the preview looks correct, click Save changes. The metric now queries Redshift live whenever it runs.

Zenskar variables reference

See every variable available in the SQL builder and what each one does.

Redshift SQL notes

Check syntax rules and unsupported functions before you write your query.

Reference

Connection detail fields

Field	Description	Example
Host	Redshift endpoint host, without the port or database suffix	`my-workgroup.123456789.us-east-1.redshift-serverless.amazonaws.com`
Port	Redshift connection port	`5439` (Redshift default)
Database name	Name of the database to connect to	`dev` (the default database)
Username	Username for the database	`prod_db`
Schema	Schema(s) that hold your tables	`public`
Password	Database password, entered raw and not URL-encoded	n/a

Network access requirements

Requirement	Detail
Reachability	Workgroup or cluster must be reachable from Zenskar, typically via Publicly accessible, or via private networking
Security group	VPC security group must allow inbound traffic on port 5439 from Zenskar’s IP address
Unknown IP or private networking	Contact your Zenskar administrator before continuing
Symptom of missing access	A connection that hangs and times out

SSL options

Setting	Standard setup	When to change
SSL connection	Enabled	Leave enabled
SSL mode	Blank	Set to `verify-ca` or `verify-full` only if full certificate verification is required
Certificate	Blank	Paste your Amazon Redshift CA certificate if using `verify-ca` or `verify-full`
Client certificate / client key	Blank	Not used by Redshift, always leave blank

Zenskar variables available in the SQL builder

Variable	Purpose
Customer External ID	Identifies the customer the metric is being evaluated for
Billing Start Date	Start of the billing period being queried
Billing End Date	End of the billing period being queried

Redshift SQL notes and limitations

Quote reserved words, such as "timestamp", in double quotes.
Redshift does not support every PostgreSQL function. Catalog helpers such as pg_table_size and obj_description are not available.
Ordinary SELECT queries against your tables work normally.

Troubleshooting

Symptom	Likely cause
Connection hangs and times out	Network access to Redshift is not fully configured (reachability or security group rule missing)
Remote datasource dropdown is empty	The data source was not created with Directly from source access
Query preview returns no rows	Test data does not fall inside the chosen billing period

Getting started

Product modules

Security

Model context protocol (MCP)

Pricing models

Third-party integrations

Roadmap

Concepts

Query directly from source

Why network access matters

How SSL fits in

How billable metrics use a remote data source

How-to guides

How to add Amazon Redshift as a data source

Connection and SSL reference

How to query Redshift from a billable metric

Zenskar variables reference

Redshift SQL notes

Reference

Connection detail fields

Network access requirements

SSL options

Zenskar variables available in the SQL builder

Redshift SQL notes and limitations

Troubleshooting

​Concepts

​Query directly from source

​Why network access matters

​How SSL fits in

​How billable metrics use a remote data source

​How-to guides

​How to add Amazon Redshift as a data source

Connection and SSL reference

​How to query Redshift from a billable metric

Zenskar variables reference

Redshift SQL notes

​Reference

​Connection detail fields

​Network access requirements

​SSL options

​Zenskar variables available in the SQL builder

​Redshift SQL notes and limitations

​Troubleshooting

Concepts

Query directly from source

Why network access matters

How SSL fits in

How billable metrics use a remote data source

How-to guides

How to add Amazon Redshift as a data source

How to query Redshift from a billable metric

Reference

Connection detail fields

Network access requirements

SSL options

Zenskar variables available in the SQL builder

Redshift SQL notes and limitations

Troubleshooting