DuckDB allows you to quickly generate synthetic data sets. To do so, you may use:
- range functions
- hash functions, e.g.,
hash,md5,sha256 - the Faker Python package via the Python function API
- using cross products (Cartesian products)
For example:
import duckdb from duckdb.typing import * from faker import Faker def random_date(): fake = Faker() return fake.date_between() duckdb.create_function("random_date", random_date, [], DATE, type="native", side_effects=True) res = duckdb.sql(""" SELECT hash(i * 10 + j) AS id, random_date() AS creationDate, IF (j % 2, true, false) FROM generate_series(1, 5) s(i) CROSS JOIN generate_series(1, 2) t(j) """) res.show() This generates the following:
┌──────────────────────┬──────────────┬─────────┐ │ id │ creationDate │ flag │ │ uint64 │ date │ boolean │ ├──────────────────────┼──────────────┼─────────┤ │ 6770051751173734325 │ 2019-11-05 │ true │ │ 16510940941872865459 │ 2002-08-03 │ true │ │ 13285076694688170502 │ 1998-11-27 │ true │ │ 11757770452869451863 │ 1998-07-03 │ true │ │ 2064835973596856015 │ 2010-09-06 │ true │ │ 17776805813723356275 │ 2020-12-26 │ false │ │ 13540103502347468651 │ 1998-03-21 │ false │ │ 4800297459639118879 │ 2015-06-12 │ false │ │ 7199933130570745587 │ 2005-04-13 │ false │ │ 18103378254596719331 │ 2014-09-15 │ false │ ├──────────────────────┴──────────────┴─────────┤ │ 10 rows 3 columns │ └───────────────────────────────────────────────┘ © 2025 DuckDB Foundation, Amsterdam NL