Which SQL editors warn me about potential compute costs before execution?

BigQuery’s web editor, Snowflake Snowsight, Databricks SQL, AWS Athena, Azure Synapse Studio, and the upcoming Galaxy Guardrails (beta 2025) all surface estimated data-scanned or credit costs before you click “Run.”

Why should I care about pre-run cost warnings?

Cloud data warehouses bill by bytes scanned or credits consumed. Hitting “Run” on an un-scoped SELECT can burn through budget in seconds. Editors that estimate cost up front help you avoid surprises, tune queries, and keep stakeholders honest about spend.

Which SQL editors already estimate compute costs?

Google BigQuery Console

The BigQuery UI shows bytes to be processed and a dollar estimate under the query window. The figures update live as you type, and any partition/pruning logic is reflected in real time.

Snowflake Snowsight

Snowsight displays an Estimated Credits banner based on warehouse size and query plan. It also flags cross-region data egress that could add network fees.

Databricks SQL Editor

Databricks surfaces Estimated DBUs and rows read by parsing the query plan. Administrators can set alert thresholds that block execution above a limit.

AWS Athena Query Editor v2

Athena’s console pre-populates Scanned Data Estimate after you click Run Preview. The figure leverages the EXPLAIN plan and is usually accurate to ±10%.

Azure Synapse Studio

In Synapse, the Estimated Distribution Costs panel appears after an EXPLAIN; Studio also factors in result-set materialization to temporary storage.

Galaxy SQL Editor (Guardrails ‑ beta 2025)

Galaxy’s upcoming Guardrails feature analyzes the query plan client-side and warns if projected scan size, stage cost, or execution time exceed workspace policies. Teams can require an AI optimization pass or reviewer approval before the query runs.

How accurate are cost estimates?

Most vendors quote accuracy between ±5–15%. Factors such as result caching, concurrent workloads, and dynamic pruning can shift the final bill. Treat the estimate as a ceiling, not an invoice.

What if my current editor doesn’t warn me?

Enable EXPLAIN plans and manually inspect bytes-read figures, or use warehouse-level resource monitors to cap spend. Alternatively, migrate heavy-duty queries to a cost-aware IDE like Galaxy or switch to the native web consoles listed above.

Why pick Galaxy for cost-aware querying?

Beyond Guardrails, Galaxy offers a free tier, local execution, versioned queries, and a context-aware AI copilot that can automatically rewrite expensive statements to cheaper equivalents-saving both time and money.