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Dark Mode
1.1 (stable)
Create Synthetic Data
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
fake = Faker()
def random_date():
return fake.date_between()
def random_short_text():
return fake.text(max_nb_chars=20)
def random_long_text():
return fake.text(max_nb_chars=200)
con = duckdb.connect()
con.create_function("random_date", random_date, [], DATE, type="native", side_effects=True)
con.create_function("random_short_text", random_short_text, [], VARCHAR, type="native", side_effects=True)
con.create_function("random_long_text", random_long_text, [], VARCHAR, type="native", side_effects=True)
res = con.sql("""
SELECT
hash(i * 10 + j) AS id,
random_date() AS creationDate,
random_short_text() AS short,
random_long_text() AS long,
IF (j % 2, true, false) AS bool
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 │
└───────────────────────────────────────────────┘