Does it support CTEs and window functions?

Yes. Common Table Expressions (WITH clauses), recursive CTEs, and window functions (ROW_NUMBER, RANK, LAG, LEAD, OVER/PARTITION BY) are all explained. The tool walks through each CTE in order so you can understand how intermediate result sets flow into the final query.

Will it flag performance issues?

It calls out likely-slow patterns: queries without a WHERE clause on a large table, missing indexes on JOIN keys, SELECT *, cartesian products from missing JOIN conditions, and OR conditions that prevent index use. For a definitive answer, always run EXPLAIN ANALYZE — the tool is a heuristic, not a query planner.

What SQL dialects are supported?

PostgreSQL, MySQL/MariaDB, SQL Server (T-SQL), BigQuery, and SQLite. Dialect-specific syntax (Postgres arrays, BigQuery STRUCTs, SQL Server TOP) is recognized. For Oracle or DB2, the explanation still works but may miss dialect-specific performance tips.

Can it convert English back to SQL?

Not this tool — it only goes SQL to English. For the reverse (natural language to SQL), tools like vanna.ai, defog, or a ChatGPT prompt with your schema are a better fit. Converting a query you already have is a different problem from authoring one from scratch.

SQL to Natural Language

Paste a SQL query — SELECT, CTE, window function, JOIN-heavy reporting query — and get a plain-English walkthrough: one-sentence summary of what the query returns, tables and joins involved, filter and grouping logic, window function behavior, and performance watch-outs (missing index, full table scan, N+1 pattern). Works for PostgreSQL, MySQL, SQL Server, BigQuery, and SQLite syntax. AI-powered.

Paste any SQL query. Get a plain-English explanation of what it returns, which tables it touches, and any performance watch-outs. Free, daily-capped.

Paste SQL0 / 5,000

Plain-English explanation

What the query returns, the tables and joins involved, filter and grouping logic, and any performance watch-outs.

What you get back

• One-sentence summary of what the query returns
• Tables, joins, and relationship breakdown
• Filter (WHERE), grouping, and ordering logic
• Window functions and CTEs explained
• Performance notes (missing indexes, full scans)
• Works for Postgres, MySQL, SQL Server, BigQuery

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Frequently Asked Questions

Does it support CTEs and window functions?: Yes. Common Table Expressions (WITH clauses), recursive CTEs, and window functions (ROW_NUMBER, RANK, LAG, LEAD, OVER/PARTITION BY) are all explained. The tool walks through each CTE in order so you can understand how intermediate result sets flow into the final query.
Will it flag performance issues?: It calls out likely-slow patterns: queries without a WHERE clause on a large table, missing indexes on JOIN keys, SELECT *, cartesian products from missing JOIN conditions, and OR conditions that prevent index use. For a definitive answer, always run <code>EXPLAIN ANALYZE</code> — the tool is a heuristic, not a query planner.
What SQL dialects are supported?: PostgreSQL, MySQL/MariaDB, SQL Server (T-SQL), BigQuery, and SQLite. Dialect-specific syntax (Postgres arrays, BigQuery STRUCTs, SQL Server TOP) is recognized. For Oracle or DB2, the explanation still works but may miss dialect-specific performance tips.
Can it convert English back to SQL?: Not this tool — it only goes SQL to English. For the reverse (natural language to SQL), tools like vanna.ai, defog, or a ChatGPT prompt with your schema are a better fit. Converting a query you already have is a different problem from authoring one from scratch.

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About SQL to Natural Language

Paste any SQL query, get a plain-English explanation of what it returns, the tables it touches, and performance watch-outs. Free, no login. This AI-backed tool sends your input to MarkdownMe's capped AI endpoint to generate the result. You choose whether we keep it to improve the tools. See the privacy page. No account is required. MarkdownMe provides free, fast, and reliable Markdown tools for developers, writers, and anyone who works with Markdown.