Test Data Without Using Production Data

Real customer data in a test system is a privacy risk. You can get realistic data without it.

Developers and testers need realistic data to find bugs, but copying production data into a test or demo system is risky. A test database usually has weaker access controls, more people can see it, and a leak of real names, emails and phone numbers can break privacy rules such as the GDPR and India's DPDP Act. There are three safer options.

The first is to mask real data. Data Masking finds personal columns such as emails, phones, names and card numbers, and replaces or hides them while keeping the shape of the file, so your tests still behave like production. Consistent masking gives the same output for the same input, so relationships between files still line up. Masking is useful when you need the real distribution of values, but remember that combined details can still identify people, so review the result.

The second is to generate data from your table definition. Paste your CREATE TABLE statement into the Schema Data Generator and it builds rows that fit every column: the right types and sizes, NOT NULL columns always filled, unique columns without repeats, auto-increment ids, and allowed-value lists from CHECK constraints. Nullable columns get about 10 percent empty values, which is useful for testing missing data. You can generate up to 500,000 rows, and set your own minimum and maximum for numbers and dates.

The third is a general random generator. The Data Generator lets you pick column types such as names, emails, addresses and dates, and download the result as CSV, JSON, Parquet or Excel. It is the fastest way to fill a demo or a screen with believable rows.

Two practical tips. Each click generates new random data, so download the file when you find a set that you want to keep and reuse it in your tests. And foreign key columns are filled with plain numbers, so load your parent table first with matching ids. All of this runs in your browser, so nothing you paste is uploaded.

Open the Schema Data Generator

Related tool pages

  • Generate Data from CREATE TABLE: Paste a CREATE TABLE and get up to 500,000 rows of realistic test data that fit every column type and rule. Free, and runs in your browser.
  • JSON Schema Data Generator: Paste a JSON Schema and generate realistic sample data that follows it: formats, enums, ranges and nested objects. Free, in your browser.

How to use the Schema Data Generator: step by step

  1. Open the Schema Data Generator.
  2. Paste your CREATE TABLE statement.
  3. Set the number of rows, up to 500,000.
  4. Generate, then download CSV, JSON, Parquet or Excel.

When to use the Schema Data Generator

  • Fill a staging database without real customer data
  • Create demo data for a presentation
  • Load-test an app with hundreds of thousands of rows
  • Test how your code handles empty values

Example

Input: CREATE TABLE users (id INT PRIMARY KEY, email VARCHAR(100), age INT);

Output: 1, ada.chen7@example.com, 34

Frequently asked questions

Which databases are supported?

CREATE TABLE from PostgreSQL, MySQL, SQL Server, Oracle and SQLite. Comments, quotes and schema names are handled.

Are foreign keys checked?

No. A foreign key column gets a number from 1 to 100, so load the parent table with ids 1 to 100 first.

Which JSON Schema versions work?

Draft 7 and newer for the common keywords listed above. Unknown keywords are ignored.

Is the data real?

No. It is random and fictional, so it is safe to share.

Tip: Download a generated file once and reuse it, so your tests run on the same data every time.