tablefaker is a versatile Python package that empowers you to effortlessly create realistic but synthetic table data for a wide range of applications. If you need to generate test data for software development, this tool simplifies the process with an intuitive schema definition in YAML format.
Schema Definition: Define your target schema using a simple YAML file. Specify the structure of your tables, column names, fake data generation code, and relationships. You can define multiple tables in a yaml file.
Faker and Randomization: Leverage the power of the Faker library and random data generation to create authentic-looking fake data that mimics real-world scenarios.
Multiple Output Formats: Generate fake data in various formats to suit your needs
- Pandas Dataframe
- Sql insert script
- CSV File
- Parquet File
- JSON File
- Excel File
pip install tablefaker
version: 1
config:
locale: en_US
python_import:
- datetime
tables:
- table_name: person
row_count: 10
columns:
- column_name: id
data: row_id
- column_name: first_name
data: fake.first_name()
- column_name: last_name
data: fake.last_name()
- column_name: age
data: fake.random_int(18, 90)
- column_name: dob
data: fake.date_of_birth()
null_percentage: 0.20
- column_name: salary
data: None # NULL
- column_name: height
data: r"170 cm" # string
- column_name: weight
data: 150 # number
- column_name: today
data: datetime.datetime.today().strftime('%Y-%m-%d') # python package
- table_name: employee
row_count: 5
columns:
- column_name: id
data: row_id
- column_name: person_id
data: fake.random_int(1, 10)
- column_name: hire_date
data: fake.date_between()
import tablefaker
# exports to current folder in csv format
tablefaker.to_csv("test_table.yaml")
# exports to sql insert into scripts to insert to your database
tablefaker.to_sql("test_table.yaml")
# exports all tables in json format
tablefaker.to_json("test_table.yaml", "./target_folder")
# exports all tables in parquet format
tablefaker.to_parquet("test_table.yaml", "./target_folder")
# exports only the first table in excel format
tablefaker.to_excel("test_table.yaml", "./target_folder/target_file.xlsx")
# get as pandas dataframes
df_dict = tablefaker.to_pandas("test_table.yaml")
person_df = df_dict["person"]
print(person_df.head(5))
You can use tablefaker in your terminal for adhoc needs or shell script to automate fake data generation.
Faker custom providers and custom functions are not supported in CLI.
# exports to current folder in csv format
tablefaker --config test_table.yaml
# exports as sql insert into script files
tablefaker --config test_table.yaml --file_type sql
# exports to current folder in excel format
tablefaker --config test_table.yaml --file_type excel
# exports all tables in json format
tablefaker --config test_table.yaml --file_type json --target ./target_folder
# exports only the first table
tablefaker --config test_table.yaml --file_type parquet --target ./target_folder/target_file.parquet
id,first_name,last_name,age,dob,salary,height,weight
1,John,Smith,35,1992-01-11,,170 cm,150
2,Charles,Shepherd,27,1987-01-02,,170 cm,150
3,Troy,Johnson,42,,170 cm,150
4,Joshua,Hill,86,1985-07-11,,170 cm,150
5,Matthew,Johnson,31,1940-03-31,,170 cm,150
INSERT INTO employee
(id,person_id,hire_date,title,salary,height,weight,school,level)
VALUES
(1, 4, '2020-10-09', 'principal engineer', NULL, '170 cm', 150, 'ISLIP HIGH SCHOOL', 'level 2'),
(2, 9, '2002-12-20', 'principal engineer', NULL, '170 cm', 150, 'GUY-PERKINS HIGH SCHOOL', 'level 1'),
(3, 2, '1996-01-06', 'principal engineer', NULL, '170 cm', 150, 'SPRINGLAKE-EARTH ELEM/MIDDLE SCHOOL', 'level 3');
You can add and use custom / community faker providers with table faker.
Here is a list of these community providers.
https://faker.readthedocs.io/en/master/communityproviders.html#
version: 1
config:
locale: en_US
tables:
- table_name: employee
row_count: 5
columns:
- column_name: id
data: row_id
- column_name: person_id
data: fake.random_int(1, 10)
- column_name: hire_date
data: fake.date_between()
- column_name: school
data: fake.school_name() # custom provider
import tablefaker
# import the custom faker provider
from faker_education import SchoolProvider
# provide the faker provider class to the tablefaker using fake_provider
# you can add a single provider or a list of providers
tablefaker.to_csv("test_table.yaml", "./target_folder", fake_provider=SchoolProvider)
# this works with all other to_ methods as well.
With Table Faker, you have the flexibility to provide your own custom functions to generate column data. This advanced feature empowers developers to create custom fake data generation logic that can pull data from a database, API, file, or any other source as needed.
You can also supply multiple functions in a list, allowing for even more versatility.
The custom function you provide should return a single value, giving you full control over your synthetic data generation.
from tablefaker import tablefaker
from faker import Faker
fake = Faker()
def get_level():
return f"level {fake.random_int(1, 5)}"
tablefaker.to_csv("test_table.yaml", "./target_folder", custom_function=get_level)
Add get_level function to your yaml file
version: 1
config:
locale: en_US
tables:
- table_name: employee
row_count: 5
columns:
- column_name: id
data: row_id
- column_name: person_id
data: fake.random_int(1, 10)
- column_name: hire_date
data: fake.date_between()
- column_name: level
data: get_level() # custom function
https://faker.readthedocs.io/en/master/providers.html#
https://github.com/necatiarslan/table-faker/issues/new
- Variables
- Foreign key
- Parquet Column Types
- Modern File Formats
- Delta Lake
- Apache Avro
- Apache Orc
- Apache Arrow
- AI
- Inline schema definition
- Json schema file
- Pyarrow table
- Use Logging package
- Exception Management
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Necati ARSLAN
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