NoiseNumeric

Add or subtract a random fraction to the original numeric value.

Parameters

Name	Description	Default	Required	Supported DB types
column	The name of the column to be affected		Yes	numeric, decimal
decimal	The decimal of the noised float value (number of digits after the decimal point)	4	No	-
min_ratio	The minimum random percentage for noise, from 0 to 1, e. g. 0.1 means "add noise up to 10%"	0.05	No	-
max_ratio	The maximum random percentage for noise, from 0 to 1, e. g. 0.1 means "add noise up to 10%"		Yes	-
min	Min threshold of noised value		No	-
max	Max threshold of noised value		No	-
engine	The engine used for generating the values [random, hash]. Use hash for deterministic generation	random	No	-

Dynamic parameters

Parameter	Supported types
min	numeric, decimal, float4, float8, int2, int4, int8
max	numeric, decimal, float4, float8, int2, int4, int8

Description

The NoiseNumeric transformer multiplies the original numeric (or decimal) value by randomly generated value that is not higher than the max_ratio parameter and not less that max_ratio parameter and adds it to or subtracts it from the original value. Additionally, you can specify the number of decimal digits by using the decimal parameter.

In case you have constraints on the numeric range, you can set the min and max parameters to specify the threshold values. The values for min and max must have the same format as the column parameter. Parameters min and max support dynamic mode. Engine parameter allows you to choose between random and hash engines for generating values. Read more about the engines

Info

If the noised value exceeds the max threshold, the transformer will set the value to max. If the noised value is lower than the min threshold, the transformer will set the value to min.

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.

Warning

Greenmask cannot parse the numeric type sitteng. For instance NUMERIC(10, 2). You should set min and max treshholds manually as well as allowed decimal. This behaviour will be changed in the later versions. Grenmask will be able to determine the decimal and scale of the column and set the min and max treshholds automatically if were not set.

Example: Adding noise to the purchase price

In this example, the original value of standardprice will be noised up to 50% and rounded up to 2 decimals.

NoiseNumeric transformer example

- schema: "purchasing"
  name: "productvendor"
  transformers:
    - name: "NoiseNumeric"
      params:
        column: "lastreceiptcost"
        max_ratio: 0.15
        decimal: 2
        max: 10000
      dynamic_params:
        min:
          column: "standardprice"

Result

Column	OriginalValue	TransformedValue
lastreceiptcost	50.2635	57.33