Join MySQL, PostgreSQL, SQL Server, Oracle, SQLite and MongoDB with your CSV and Excel files in plain SQL. When the answer is a fix, Varan writes it back to the source — only the rows that changed, in one transaction — and PLAN shows you every one of them first. Nothing is installed on your database servers, and your data never leaves your network.
-- Revenue against target: PostgreSQL × MySQL × Excel
SELECT a.region, SUM(o.total) AS revenue, t.target
FROM shop__orders o -- PostgreSQL
JOIN crm__accounts a ON a.id = o.account_id -- MySQL
JOIN targets t ON t.region = a.region -- targets.xlsx
GROUP BY a.region, t.target;macOS · Windows · Free during the beta · free account required
Every source below becomes a table in the same workspace, and any two of them can appear in the same JOIN.
native drivers
PostgreSQL · MySQL · MariaDB · SQL Server · Oracle · SQLite
schema discovered, not guessed
MongoDB
presets over the Postgres / MySQL wire protocol
Neon · Supabase · CockroachDB · Amazon Redshift · TimescaleDB · PlanetScale · TiDB Cloud
queryable as ordinary tables
CSV · Excel · DuckDB
What is Varan?
Varan is a desktop SQL client that runs one SQL query across different databases and files — JOIN a MySQL table to a PostgreSQL table to a CSV or Excel file in a single query, powered by a local-first DuckDB engine, with no ETL. When the answer is a fix, it writes it back to the source — only the rows that changed, in one transaction — and PLAN shows every row first. It also adds anomaly detection, lineage and git-style rollback. Varan is a proprietary desktop app, free during the beta.
How do I join tables from different databases?
Point Varan at each source and run one SQL query with a normal JOIN across MySQL, PostgreSQL, DuckDB and spreadsheets. The join runs on your machine with the access you already have — no ETL, no copying into one database first. Read the full guide →
Is Varan a DBeaver alternative?
Yes — it's a desktop SQL client like DBeaver, but it can join across different databases and files in a single query, and adds a Python surface, anomaly detection, lineage and git-style rollback. Varan vs DBeaver →
Can I query MySQL and PostgreSQL together?
Yes — one SQL statement joins a MySQL table to a PostgreSQL table (and to CSV or Excel files) without importing everything into one database.
Can I query MongoDB with SQL?
Yes — a collection becomes an ordinary SQL table. Nested fields like addr.city become normal columns, arrays of scalars become native list columns you can unnest, and you can JOIN the collection straight to a PostgreSQL or MySQL table. How it works →
How does Varan know a collection's schema?
It counts instead of guessing. Most tools infer a schema from a sample of documents and silently miss whatever the sample didn't contain. Varan reads every document once and counts every field, type, presence count and array element type — on your machine, at 83× less server CPU than aggregating there. On 25,000 real GitHub events that recovered 100% of 909 fields; sampling the first 500 documents missed 154 of the 346 rare ones entirely. See the benchmark →
What if a field has more than one type?
It is never silently coerced. Varan reads it as text and shows the exact evidence — how many documents used each type. A write to it is refused rather than guessed, with the clause that settles it: TYPES (amount AS STRING). Across 492,000 real documents, one column needed that.
Do I need admin access or a pipeline?
No — Varan runs on your machine with the database accounts you already have. No ETL, no exports, nothing installed on your servers. A query only reads; Varan writes to a source only when you run a write, and PLAN shows it first.
Learn more: MongoDB as SQL · Query MongoDB with SQL · Schema-inference benchmark · Cross-source SQL · Anomaly detection · Column-level lineage · Data version control · Database rollback · vs DBeaver · vs DataGrip · vs TablePlus
Varan is experimental beta software that can write to your databases — keep backups and try it on something that is not production first. Terms of Service · Privacy Policy