Skip to main content
Version: Next

RandomDate

Generate a random date in a specified interval.

Parameters

NameDescriptionDefaultRequiredSupported DB types
columnName of the column to be affectedYesdate, timestamp, timestamptz
minThe minimum threshold date for the random value. The format depends on the column type.Yes-
maxThe maximum threshold date for the random value. The format depends on the column type.Yes-
truncateTruncate the date to the specified part (nanosecond, microsecond, millisecond, second, minute, hour, day, month, year). The truncate operation is not applied by default.No-
keep_nullIndicates whether NULL values should be replaced with transformed values or nottrueNo-
engineThe engine used for generating the values [random, hash]. Use hash for deterministic generationrandomNo-

Dynamic parameters

ParameterSupported types
mindate, timestamp, timestamptz
maxdate, timestamp, timestamptz

Description

The RandomDate transformer generates a random date within the provided interval, starting from min to max. It can also perform date truncation up to the specified part of the date. The format of dates in the min and max parameters must adhere to PostgreSQL types, including DATE, TIMESTAMP WITHOUT TIMEZONE, or TIMESTAMP WITH TIMEZONE.

note

The value of min and max parameters depends on the column type. For example, for the date column, the value should be in the format YYYY-MM-DD, while for the timestamp column, the value should be in the format YYYY-MM-DD HH:MM:SS or YYYY-MM-DD HH:MM:SS.SSSSSS. The timestamptz column requires the value to be in the format YYYY-MM-DD HH:MM:SS.SSSSSS+HH:MM. Read more about date/time formats in the PostgreSQL documentation.

The behaviour for NULL values can be configured using the keep_null parameter. The engine parameter allows you to choose between random and hash engines for generating values. Read more about the engines in the Transformation engines section.

Example: Generate modifieddate

In the following example, a random timestamp without timezone is generated for the modifieddate column within the range from 2011-05-31 00:00:00 to 2013-05-31 00:00:00, and the part of the random value after day is truncated.

RandomDate transformer example
- schema: "sales"
name: "salesorderdetail"
transformers:
- name: "RandomDate"
params:
column: "modifieddate"
keep_null: false
min: "2011-05-31 00:00:00"
max: "2013-05-31 00:00:00"
truncate: "day"

Result

ColumnOriginalValueTransformedValue
modifieddate2014-06-30 00:00:002012-07-27 00:00:00

Example: Generate hiredate based on birthdate using two transformations

In this example, the RandomDate transformer generates a random date for the birthdate column within the range now - 50 years to now - 18 years. The hire date is generated based on the birthdate, ensuring that the employee is at least 18 years old when hired.

- schema: "humanresources"
name: "employee"
transformers:
- name: "RandomDate"
params:
column: "birthdate"
min: '{{ now | tsModify "-50 years" | .EncodeValue }}' # 1994
max: '{{ now | tsModify "-18 years" | .EncodeValue }}' # 2006

- name: "RandomDate"
params:
column: "hiredate"
truncate: "month"
max: "{{ now | .EncodeValue }}"
dynamic_params:
min:
column: "birthdate"
template: '{{ .GetValue | tsModify "18 years" | .EncodeValue }}' # min age 18 years

Result:

ColumnOriginalValueTransformedValue
birthdate1969-01-291985-10-29
hiredate2009-01-142023-01-01
Copyright © GreenMask 2026