DuckDB · supported engine

DuckDB, analytical and embedded.

An embedded analytical workbench with SQLite-family UI parity — isolated transactions, transactional migrations, physical backup/restore, and remote import from Parquet, CSV, and cloud storage.

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Embedded · local files · remote import

Live · click to inspect

The pipeline Mongrel would build for your query.

Click any operator below to see cardinality, pushdown behavior, and what Mongrel would suggest. Same view you get inside the workbench.

// SEQ_SCAN · orders/*.csv

Reads all 92M rows and all 14 columns from CSV — only 3 columns are used. No projection or filter pushdown, types re-inferred per file.

-- analytics.duckdb · orders lake
SELECT
  u.region,
  count(*) AS orders,
  sum(o.total) AS revenue
FROM read_csv('s3://lake/orders/*.csv',
       auto_detect = true) o
JOIN users u ON u.id = o.user_id
WHERE o.order_date >= DATE '2026-01-01'
GROUP BY u.region
ORDER BY revenue DESC;

-- 41.2s · 92M rows scanned, 14 columns read, 3 used
-- ✓ Proposal: partitioned Parquet + pushed-down filter

COPY (SELECT user_id, total, order_date
        FROM read_csv('s3://lake/orders/*.csv'))
TO 'lake/orders_parquet'
  (FORMAT PARQUET, PARTITION_BY (year(order_date)));

DuckDB surface

What Mongrel ships for DuckDB.

Visual query builder

Build analytical SELECTs, joins, and aggregations visually. Output is real DuckDB SQL — both sides stay editable.

EXPLAIN pipeline viewer

Run EXPLAIN and walk the physical pipeline operator by operator: PROJECTION, HASH_GROUP_BY, HASH_JOIN, scans, with per-operator cardinalities.

Parquet, CSV & remote import

Query Parquet, CSV, and JSON in place — local files, globs, S3, or HTTPS. Import wizards land remote data in native tables.

Isolated transactions

Concurrent connections get snapshot-isolated transactions on the same embedded file. Explicit BEGIN, COMMIT, and ROLLBACK from the UI.

Transactional migrations

Schema changes run inside a transaction and roll back cleanly on failure. Compare schemas and generate reversible migration scripts.

Physical backup & restore

Copy-on-write checkpoints and file-level backup of the .duckdb database, with restore and attach/detach workflows.

SQLite-family UI parity

The same table browser, row editor, and schema panels you know from SQLite — DuckDB is embedded, so the workflow feels identical.

Aggregations & window functions

First-class support for DuckDB's analytical SQL: GROUPING SETS, window functions, list and struct types, and sampling.

Copy between engines

Land query results or whole tables into PostgreSQL, SQLite, or any other engine — schema-aware, in both directions.

Open your first DuckDB file in 30 seconds.

7-day trial. macOS, Windows, Linux. No credit card.

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