A fast data generator that produces CSV files from generated relational data.
Find the release that matches your architecture on the releases page.
Download the tar, extract the executable, and move it into your PATH:
$ tar -xvf dg_[VERSION]-rc1_macOS.tar.gz
$ dg
Usage dg:
-c string
the absolute or relative path to the config file
-cpuprofile string
write cpu profile to file
-i string
write import statements to file
-o string
the absolute or relative path to the output dir (default ".")
-p int
port to serve files from (omit to generate without serving)
-version
display the current version number
Create a config file. In the following example, we create 10,000 people, 50 events, 5 person types, and then populate the many-to-many person_event
resolver table with 500,000 rows that represent the Cartesian product between the person and event tables:
tables:
- name: person
count: 10000
columns:
# Generate a random UUID for each person
- name: id
type: gen
processor:
value: ${uuid}
- name: event
count: 50
columns:
# Generate a random UUID for each event
- name: id
type: gen
processor:
value: ${uuid}
- name: person_type
count: 5
columns:
# Generate a random UUID for each person_type
- name: id
type: gen
processor:
value: ${uuid}
# Generate a random 16 bit number and left-pad it to 5 digits
- name: name
type: gen
processor:
value: ${uint16}
format: "%05d"
- name: person_event
columns:
# Generate a random UUID for each person_event
- name: id
type: gen
processor:
value: ${uuid}
# Select a random id from the person_type table
- name: person_type
type: ref
processor:
table: person_type
column: id
# Generate a person_id column for each id in the person table
- name: person_id
type: each
processor:
table: person
column: id
# Generate an event_id column for each id in the event table
- name: event_id
type: each
processor:
table: event
column: id
Run the application:
$ dg -c your_config_file.yaml -o your_output_dir -p 3000
loaded config file took: 428µs
generated table: person took: 41ms
generated table: event took: 159µs
generated table: person_type took: 42µs
generated table: person_event took: 1s
generated all tables took: 1s
wrote csv: person took: 1ms
wrote csv: event took: 139µs
wrote csv: person_type took: 110µs
wrote csv: person_event took: 144ms
wrote all csvs took: 145ms
This will output and dg will then run an HTTP server allow you to import the files from localhost.
your_output_dir
├── event.csv
├── person.csv
├── person_event.csv
└── person_type.csv
Then import the files as you would any other; here's an example insert into CockroachDB:
IMPORT INTO "person" ("id")
CSV DATA (
'https://localhost:3000/person.csv'
)
WITH skip='1', nullif = '', allow_quoted_null;
IMPORT INTO "event" ("id")
CSV DATA (
'https://localhost:3000/event.csv'
)
WITH skip='1', nullif = '', allow_quoted_null;
IMPORT INTO "person_type" ("id", "name")
CSV DATA (
'https://localhost:3000/person_type.csv'
)
WITH skip='1', nullif = '', allow_quoted_null;
IMPORT INTO "person_event" ("person_id", "event_id", "id", "person_type")
CSV DATA (
'https://localhost:3000/person_event.csv'
)
WITH skip='1', nullif = '', allow_quoted_null;
If you're working with a remote database and have access to the psql
binary, try importing the CSV file as follows:
psql "postgres:https://root@localhost:26257/defaultdb?sslmode=disable" \
-c "\COPY public.person (id, full_name, date_of_birth, user_type, favourite_animal) FROM './csvs/person/person.csv' WITH DELIMITER ',' CSV HEADER NULL E''"
If you're working with a remote database and have access to the cockroach
binary, try importing the CSV file as follows:
cockroach nodelocal upload ./csvs/person/person.csv imports/person.csv \
--url "postgres:https://root@localhost:26257?sslmode=disable"
Then importing the file as follows:
IMPORT INTO person ("id", "full_name", "date_of_birth", "user_type", "favourite_animal")
CSV DATA (
'nodelocal:https://1/imports/person.csv'
) WITH skip = '1';
Table elements instruct dg to generate data for a single table and output it as a csv file. Here are the configuration options for a table:
tables:
- name: person
unique_columns: [col_a, col_b]
count: 10
columns: ...
This config generates 10 random rows for the person table. Here's a breakdown of the fields:
Field Name | Optional | Description |
---|---|---|
name | No | Name of the table. Must be unique. |
unique_columns | Yes | Removes duplicates from the table based on the column names provided |
count | Yes | If provided, will determine the number of rows created. If not provided, will be calculated by the current table size. |
suppress | Yes | If true the table won't be written to a CSV. Useful when you need to generate intermediate tables to combine data locally. |
columns | No | A collection of columns to generate for the table. |
dg takes its configuration from a config file that is parsed in the form of an object containing arrays of objects; tables
and inputs
. Each object in the tables
array represents a CSV file to be generated for a named table and contains a collection of columns to generate data for.
Generate a random value for the column. Here's an example:
- name: sku
type: gen
processor:
value: SKU${uint16}
format: "%05d"
This configuration will generate a random left-padded uint16
with a prefix of "SKU" for a column called "sku". value
contains zero or more function placeholders that can be used to generate data. A list of available functions can be found here.
Generate a pattern-based value for the column. Here's an example:
- name: phone
type: gen
processor:
pattern: \d{3}-\d{3}-\d{4}
This configuration will generate US-format phone number, like 123-456-7890.
Provide a constant set of values for a column. Here's an example:
- name: options
type: const
processor:
values: [bed_breakfast, bed]
This configuration will create a column containing two rows.
Select a value from a given set. Here's an example:
- name: user_type
type: set
processor:
values: [admin, regular, read-only]
This configuration will select between the values "admin", "regular", and "read-only"; each with an equal probability of being selected.
Items in a set can also be given a weight, which will affect their likelihood of being selected. Here's an example:
- name: favourite_animal
type: set
processor:
values: [rabbit, dog, cat]
weights: [10, 60, 30]
This configuration will select between the values "rabbit", "dog", and "cat"; each with different probabilities of being selected. Rabbits will be selected approximately 10% of the time, dogs 60%, and cats 30%. The total value doesn't have to be 100, however, you can use whichever numbers make most sense to you.
Generates an incrementing number. Here's an example:
- name: id
type: inc
processor:
start: 1
format: "P%03d"
This configuration will generate left-padded ids starting from 1, and format them with a prefix of "P".
References a value from a previously generated table. Here's an example:
- name: ptype
type: ref
processor:
table: person_type
column: id
This configuration will choose a random id from the person_type table and create a ptype
column to store the values.
Use the ref
type if you need to reference another table but don't need to generate a new row for every instance of the referenced column.
Creates a row for each value in another table. If multiple each
columns are provided, a Cartesian product of both columns will be generated.
Here's an example of one each
column:
- name: person
count: 3
columns:
- name: id
type: gen
processor:
value: ${uuid}
# person
#
# id
# c40819f8-2c76-44dd-8c44-5eef6a0f2695
# 58f42be2-6cc9-4a8c-b702-c72ab1decfea
# ccbc2244-667b-4bb5-a5cd-a1e9626a90f9
- name: pet
columns:
- name: person_id
type: each
processor:
table: person
column: id
- name: name
type: gen
processor:
value: first_name
# pet
#
# person_id name
# c40819f8-2c76-44dd-8c44-5eef6a0f2695 Carlo
# 58f42be2-6cc9-4a8c-b702-c72ab1decfea Armando
# ccbc2244-667b-4bb5-a5cd-a1e9626a90f9 Kailey
Here's an example of two each
columns:
- name: person
count: 3
columns:
- name: id
type: gen
processor:
value: ${uuid}
# person
#
# id
# c40819f8-2c76-44dd-8c44-5eef6a0f2695
# 58f42be2-6cc9-4a8c-b702-c72ab1decfea
# ccbc2244-667b-4bb5-a5cd-a1e9626a90f9
- name: event
count: 3
columns:
- name: id
type: gen
processor:
value: ${uuid}
# event
#
# id
# 39faeb54-67d1-46db-a38b-825b41bfe919
# 7be981a9-679b-432a-8a0f-4a0267170c68
# 9954f321-8040-4cd7-96e6-248d03ee9266
- name: person_event
columns:
- name: person_id
type: each
processor:
table: person
column: id
- name: event_id
type: each
processor:
table: event
column: id
# person_event
#
# person_id
# c40819f8-2c76-44dd-8c44-5eef6a0f2695 39faeb54-67d1-46db-a38b-825b41bfe919
# c40819f8-2c76-44dd-8c44-5eef6a0f2695 7be981a9-679b-432a-8a0f-4a0267170c68
# c40819f8-2c76-44dd-8c44-5eef6a0f2695 9954f321-8040-4cd7-96e6-248d03ee9266
# 58f42be2-6cc9-4a8c-b702-c72ab1decfea 39faeb54-67d1-46db-a38b-825b41bfe919
# 58f42be2-6cc9-4a8c-b702-c72ab1decfea 7be981a9-679b-432a-8a0f-4a0267170c68
# 58f42be2-6cc9-4a8c-b702-c72ab1decfea 9954f321-8040-4cd7-96e6-248d03ee9266
# ccbc2244-667b-4bb5-a5cd-a1e9626a90f9 39faeb54-67d1-46db-a38b-825b41bfe919
# ccbc2244-667b-4bb5-a5cd-a1e9626a90f9 7be981a9-679b-432a-8a0f-4a0267170c68
# ccbc2244-667b-4bb5-a5cd-a1e9626a90f9 9954f321-8040-4cd7-96e6-248d03ee9266
Use the each
type if you need to reference another table and need to generate a new row for every instance of the referenced column.
Generates data within a given range. Note that a number of factors determine how this generator will behave. The step (and hence, number of rows) will be generated in the following priority order:
- If an
each
generator is being used, step will be derived from that - If a
count
is provided, step will be derived from that - Otherwise,
step
will be used
Here's an example that generates monotonically increasing ids for a table, starting from 1:
- name: users
count: 10000
columns:
- name: id
type: range
processor:
type: int
from: 1
step: 1
Here's an example that generates all dates between 2020-01-01
and 2023-01-01
at daily intervals:
- name: event
columns:
- name: date
type: range
processor:
type: date
from: 2020-01-01
to: 2023-01-01
step: 24h
format: 2006-01-02
Here's an example that generates 10 dates between 2020-01-01
and 2023-01-02
:
- name: event
count: 10
columns:
- name: date
type: range
processor:
type: date
from: 2020-01-01
to: 2023-01-01
format: 2006-01-02
step: 24h # Ignored due to table count.
Here's an example that generates 20 dates (one for every row found from an each
generator) between 2020-01-01
and 2023-01-02
:
- name: person
count: 20
columns:
- name: id
type: gen
processor:
value: ${uuid}
- name: event
count: 10 # Ignored due to resulting count from "each" generator.
columns:
- name: person_id
type: each
processor:
table: person
column: id
- name: date
type: range
processor:
type: date
from: 2020-01-01
to: 2023-01-01
format: 2006-01-02
The range generate currently supports the following data types:
date
- Generate dates between a from and to valueint
- Generate integers between a from and to value
Generates data by matching data in another table. In this example, we'll assume there's a CSV file for the significant_event
input that generates the following table:
date | event |
---|---|
2023-01-10 | abc |
2023-01-11 | |
2023-01-12 | def |
inputs:
- name: significant_event
type: csv
source:
file_name: significant_dates.csv
tables:
- name: events
columns:
- name: timeline_date
type: range
processor:
type: date
from: 2023-01-09
to: 2023-01-13
format: 2006-01-02
step: 24h
- name: timeline_event
type: match
processor:
source_table: significant_event
source_column: date
source_value: events
match_column: timeline_date
dg will match rows in the significant_event table with rows in the events table based on the match between significant_event.date
and events.timeline_date
, and take the value from the significant_events.event
column where there's a match (otherwise leaving NULL
). This will result in the following events
table being generated:
timeline_date | timeline_event |
---|---|
2023-01-09 | |
2023-01-10 | abc |
2023-01-11 | |
2023-01-12 | def |
2023-01-13 |
dg takes its configuration from a config file that is parsed in the form of an object containing arrays of objects; tables
and inputs
. Each object in the inputs
array represents a data source from which a table can be created. Tables created via inputs will not result in output CSVs.
Reads in a CSV file as a table that can be referenced from other tables. Here's an example:
- name: significant_event
type: csv
source:
file_name: significant_dates.csv
This configuration will read from a file called significant_dates.csv and create a table from its contents. Note that the file_name
should be relative to the config directory, so if your CSV file is in the same directory as your config file, just include the file name.
Name | Type | Example |
---|---|---|
${ach_account} | string | 586981797546 |
${ach_routing} | string | 441478502 |
${adjective_demonstrative} | string | there |
${adjective_descriptive} | string | eager |
${adjective_indefinite} | string | several |
${adjective_interrogative} | string | whose |
${adjective_possessive} | string | her |
${adjective_proper} | string | Iraqi |
${adjective_quantitative} | string | sufficient |
${adjective} | string | double |
${adverb_degree} | string | far |
${adverb_frequency_definite} | string | daily |
${adverb_frequency_indefinite} | string | always |
${adverb_manner} | string | unexpectedly |
${adverb_place} | string | here |
${adverb_time_definite} | string | yesterday |
${adverb_time_indefinite} | string | just |
${adverb} | string | far |
${animal_type} | string | mammals |
${animal} | string | ape |
${app_author} | string | RedLaser |
${app_name} | string | SlateBlueweek |
${app_version} | string | 3.2.10 |
${bitcoin_address} | string | 16YmZ5ol5aXKjilZT2c2nIeHpbq |
${bitcoin_private_key} | string | 5JzwyfrpHRoiA59Y1Pd9yLq52cQrAXxSNK4QrGrRUxkak5Howhe |
${bool} | bool | true |
${breakfast} | string | Awesome orange chocolate muffins |
${bs} | string | leading-edge |
${car_fuel_type} | string | LPG |
${car_maker} | string | Seat |
${car_model} | string | Camry Solara Convertible |
${car_transmission_type} | string | Manual |
${car_type} | string | Passenger car mini |
${chrome_user_agent} | string | Mozilla/5.0 (X11; Linux i686) AppleWebKit/5310 (KHTML, like Gecko) Chrome/37.0.882.0 Mobile Safari/5310 |
${city} | string | Memphis |
${color} | string | DarkBlue |
${company_suffix} | string | LLC |
${company} | string | PlanetEcosystems |
${connective_casual} | string | an effect of |
${connective_complaint} | string | i.e. |
${connective_examplify} | string | for example |
${connective_listing} | string | next |
${connective_time} | string | soon |
${connective} | string | for instance |
${country_abr} | string | VU |
${country} | string | Eswatini |
${credit_card_cvv} | string | 315 |
${credit_card_exp} | string | 06/28 |
${credit_card_type} | string | Mastercard |
${currency_long} | string | Mozambique Metical |
${currency_short} | string | SCR |
${date} | time.Time | 2005-01-25 22:17:55.371781952 +0000 UTC |
${day} | int | 27 |
${dessert} | string | Chocolate coconut dream bars |
${dinner} | string | Creole potato salad |
${domain_name} | string | centralb2c.net |
${domain_suffix} | string | com |
${email} | string | [email protected] |
${emoji} | string | ♻️ |
${file_extension} | string | csv |
${file_mime_type} | string | image/vasa |
${firefox_user_agent} | string | Mozilla/5.0 (X11; Linux x86_64; rv:6.0) Gecko/1951-07-21 Firefox/37.0 |
${first_name} | string | Kailee |
${flipacoin} | string | Tails |
${float32} | float32 | 2.7906555e+38 |
${float64} | float64 | 4.314310154193861e+307 |
${fruit} | string | Eggplant |
${gender} | string | female |
${hexcolor} | string | #6daf06 |
${hobby} | string | Bowling |
${hour} | int | 18 |
${http_method} | string | DELETE |
${http_status_code_simple} | int | 404 |
${http_status_code} | int | 503 |
${http_version} | string | HTTP/1.1 |
${int16} | int16 | 18940 |
${int32} | int32 | 2129368442 |
${int64} | int64 | 5051946056392951363 |
${int8} | int8 | 110 |
${ipv4_address} | string | 191.131.155.85 |
${ipv6_address} | string | 1642:94b:52d8:3a4e:38bc:4d87:846e:9c83 |
${job_descriptor} | string | Senior |
${job_level} | string | Identity |
${job_title} | string | Executive |
${language_abbreviation} | string | kn |
${language} | string | Bengali |
${last_name} | string | Friesen |
${latitude} | float64 | 45.919913 |
${longitude} | float64 | -110.313125 |
${lunch} | string | Sweet and sour pork balls |
${mac_address} | string | bd:e8:ce:66:da:5b |
${minute} | int | 23 |
${month_string} | string | April |
${month} | int | 10 |
${name_prefix} | string | Ms. |
${name_suffix} | string | I |
${name} | string | Paxton Schumm |
${nanosecond} | int | 349669923 |
${nicecolors} | []string | [#490a3d #bd1550 #e97f02 #f8ca00 #8a9b0f] |
${noun_abstract} | string | timing |
${noun_collective_animal} | string | brace |
${noun_collective_people} | string | mob |
${noun_collective_thing} | string | orchard |
${noun_common} | string | problem |
${noun_concrete} | string | town |
${noun_countable} | string | cat |
${noun_uncountable} | string | wisdom |
${noun} | string | case |
${opera_user_agent} | string | Opera/10.10 (Windows NT 5.01; en-US) Presto/2.11.165 Version/13.00 |
${password} | string | 1k0vWN 9Z |
${pet_name} | string | Bernadette |
${phone_formatted} | string | (476)455-2253 |
${phone} | string | 2692528685 |
${phrase} | string | I'm straight |
${preposition_compound} | string | ahead of |
${preposition_double} | string | next to |
${preposition_simple} | string | at |
${preposition} | string | outside of |
${programming_language} | string | PL/SQL |
${pronoun_demonstrative} | string | those |
${pronoun_interrogative} | string | whom |
${pronoun_object} | string | us |
${pronoun_personal} | string | I |
${pronoun_possessive} | string | mine |
${pronoun_reflective} | string | yourself |
${pronoun_relative} | string | whom |
${pronoun} | string | those |
${quote} | string | "Raw denim tilde cronut mlkshk photo booth kickstarter." - Gunnar Rice |
${rgbcolor} | []int | [152 74 172] |
${safari_user_agent} | string | Mozilla/5.0 (Windows; U; Windows 95) AppleWebKit/536.41.5 (KHTML, like Gecko) Version/5.2 Safari/536.41.5 |
${safecolor} | string | gray |
${second} | int | 58 |
${snack} | string | Crispy fried chicken spring rolls |
${ssn} | string | 783135577 |
${state_abr} | string | AL |
${state} | string | Kentucky |
${street_name} | string | Way |
${street_number} | string | 6234 |
${street_prefix} | string | Port |
${street_suffix} | string | stad |
${street} | string | 11083 Lake Fall mouth |
${time_zone_abv} | string | ADT |
${time_zone_full} | string | (UTC-02:00) Coordinated Universal Time-02 |
${time_zone_offset} | float32 | 3 |
${time_zone_region} | string | Asia/Aqtau |
${time_zone} | string | Mountain Standard Time (Mexico) |
${uint128_hex} | string | 0xcd50930d5bc0f2e8fa36205e3d7bd7b2 |
${uint16_hex} | string | 0x7c80 |
${uint16} | uint16 | 25076 |
${uint256_hex} | string | 0x61334b8c51fa841bf9a3f1f0ac3750cd1b51ca2046b0fb75627ac73001f0c5aa |
${uint32_hex} | string | 0xfe208664 |
${uint32} | uint32 | 783098878 |
${uint64_hex} | string | 0xc8b91dc44e631956 |
${uint64} | uint64 | 5722659847801560283 |
${uint8_hex} | string | 0x65 |
${uint8} | uint8 | 192 |
${url} | string | https://www.leadcutting-edge.net/productize |
${user_agent} | string | Opera/10.64 (Windows NT 5.2; en-US) Presto/2.13.295 Version/10.00 |
${username} | string | Gutmann2845 |
${uuid} | string | e6e34ff4-1def-41e5-9afb-f697a51c0359 |
${vegetable} | string | Tomato |
${verb_action} | string | knit |
${verb_helping} | string | did |
${verb_linking} | string | has |
${verb} | string | be |
${weekday} | string | Tuesday |
${word} | string | month |
${year} | int | 1962 |
${zip} | string | 45618 |
$ VERSION=0.1.0 make release
Thanks to the maintainers of the following fantastic packages, whose code this tools makes use of:
- Improve code coverage
- Write file after generating, then only keep columns that other tables need
- Support for range without a table count (e.g. the following results in zero rows unless a count is provided)
- name: bet_types
count: 3
columns:
- name: id
type: range
processor:
type: int
from: 1
step: 1
- name: description
type: const
processor:
values: [Win, Lose, Draw]