SQL & KQL Linter
Detect anti-patterns, performance issues, and best practice violations in your queries. Everything runs in your browser — nothing is sent to a server.
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Client-side only
Your queries never leave your browser. All analysis is performed locally using JavaScript.
Multiple dialects
Supports T-SQL, Standard SQL, PL/SQL, MySQL, PostgreSQL, and KQL (Kusto Query Language).
27 lint rules
Detects anti-patterns, missing WHERE clauses, non-SARGable predicates, unused CTEs, and KQL-specific issues.
What the SQL and KQL linter checks
The linter provides fast static feedback before a query reaches production. Findings are guidance for review—not a replacement for testing against real data, statistics, permissions, and execution plans.
When to use it
- Spot destructive statements and UPDATE or DELETE operations without filters.
- Find common non-SARGable predicates and query-maintenance problems.
- Review SQL and KQL consistently without uploading proprietary query text.
- Use rule identifiers to discuss findings during code review.
Continue with the database tools directory, browse technical articles, or check the SQL Server release tracker.