---
title: "Protect Performance and Reduce Surprise Costs with Default Warehouse"
description: "Databricks SQL’s generally available Default Warehouse lets administrators choose the SQL warehouse automatically used for ad hoc experiences, addressing manual selection and fallback behavior such as “Last Selected” or alphabetical ordering. A workspace-level setting applies across SQL Editor, Catalog Explorer, AI/BI Dashboards, Alerts, and Genie Spaces, while users can override it or retain “Last Selected”; admin APIs and a Terraform resource support per-user assignment, auditing, and control. The feature supports serverless, pro, and classic SQL warehouses and respects existing governance and access controls, with the setting opt-in and new assets automatically using it. In customer results, Catalog Explorer queries sent to smaller warehouses rose from 77% to 96%, and users running ad hoc SQL across multiple warehouses fell by 15%, while future coverage is planned for MLflow, Lakeflow CLI, and DBSQL MCP."
---

# Protect Performance and Reduce Surprise Costs with Default Warehouse

[Databricks](https://yomu.fyi/company/databricks) · JooHo Yeo, Gabriel Dutra Dias · Sep 18, 2026

**Type:** Announcement

## Summary

Databricks SQL’s generally available Default Warehouse lets administrators choose the SQL warehouse automatically used for ad hoc experiences, addressing manual selection and fallback behavior such as “Last Selected” or alphabetical ordering. A workspace-level setting applies across SQL Editor, Catalog Explorer, AI/BI Dashboards, Alerts, and Genie Spaces, while users can override it or retain “Last Selected”; admin APIs and a Terraform resource support per-user assignment, auditing, and control. The feature supports serverless, pro, and classic SQL warehouses and respects existing governance and access controls, with the setting opt-in and new assets automatically using it. In customer results, Catalog Explorer queries sent to smaller warehouses rose from 77% to 96%, and users running ad hoc SQL across multiple warehouses fell by 15%, while future coverage is planned for MLflow, Lakeflow CLI, and DBSQL MCP.

## Context

Ad hoc queries previously required users to select a warehouse manually, with the system otherwise falling back to “Last Selected” or alphabetical ordering. This could send exploratory work to production warehouses, causing resource contention, unnecessary warehouse starts, and less predictable costs.

## Approach / What changed

Administrators configure one workspace-level default SQL warehouse in Workspace Settings → Compute. Users can follow that default, override it, or choose “Last Selected”; admin APIs add per-user assignment, auditing, and control, and the API is also available as a Terraform resource.

## Takeaways

- The workspace default applies to ad hoc SQL surfaces including SQL Editor, Catalog Explorer, AI/BI Dashboards, Alerts, and Genie Spaces.
- Users can override the workspace choice or select “Last Selected,” while administrators can inspect and manage user-level defaults through APIs.
- Where admins selected a smaller default warehouse, Catalog Explorer queries using smaller warehouses increased from 77% to 96%; multi-warehouse ad hoc usage fell by 15%.

## FAQ

### Which SQL warehouse types can be selected as a Default Warehouse?

Default Warehouse supports serverless, pro, and classic SQL warehouses. The feature respects existing governance and access controls.

### Can users choose a different warehouse from the workspace default?

Yes. Users can follow the workspace default, override it with another warehouse, or choose “Last Selected.” Administrators can view and control user-level overrides through APIs.

### What evidence shows that Default Warehouse reduces unnecessary warehouse selection?

In workspaces using a smaller default, Catalog Explorer queries sent to smaller warehouses increased from 77% to 96%. The number of users running ad hoc SQL across multiple warehouses decreased by 15%.

**Tags:** [Databricks](https://yomu.fyi/topic/databricks), [SQL](https://yomu.fyi/topic/sql), [Terraform](https://yomu.fyi/topic/terraform)

- Source: [Databricks](https://www.databricks.com/blog/protect-performance-and-reduce-surprise-costs-default-warehouse)
- Source URL: https://www.databricks.com/blog/protect-performance-and-reduce-surprise-costs-default-warehouse
- Ingested by Yomu: 2026-09-17T14:06:34.342Z

[Read original post](https://www.databricks.com/blog/protect-performance-and-reduce-surprise-costs-default-warehouse)