Karan Sharma

Ramblings on tech, cycling, and finance

Generate Million Rows

I wanted a quick way to generate some random data in a PostgreSQL database and insert 1mn rows.

The following query shows how to generate a UUIDv4 and insert 1mn rows:

INSERT INTO table (uuid, name)
SELECT uuid_in(overlay(overlay(md5(random()::text || ':' || clock_timestamp()::text) placing '4' from 13) placing to_hex(floor(random()*(11-8+1) + 8)::int)::text from 17)::cstring), 'load tests'
FROM generate_series(1, 1000000);