How Null Values Work in Decision Tables

Use the Consider Null Values for Lookup option to handle the behavior of how rows with null values are treated during lookup. When you enable this option, rows with null values in the decision table are matched only when the input explicitly includes null, which ensures precise matches. When you disable this option, and any of the rows have null values, then the column values that pertain to the null value are also considered as null.

Required Editions

Available in: Lightning Experience

Available in: Enterprise, Unlimited, and Developer Editions for clouds that have Business Rules Engine enabled

Note Decision tables consider null values for the input conditions that are mandatory and have the operator set as Equal.

Example Consider the scenario where a decision table has input and output columns per this table:

INPUT			OUTPUT
Product	Payment type	Price	Discount
A	one-time	1000	5
B	null	500	10
B	one-time	500	15

When Consider Null Values for Lookup is enabled, the output matches a null input to the explicit null value in the payment type column. When Consider Null Values for Lookup is disabled, the output matches a null input to all the values in the payment type column. Here is a table that compares the outputs for when Consider Null Values for Lookup is enabled and disabled.

Product	Payment Type	Price	Output with Consider Null Values for Lookup Enabled	Output with Consider Null Values for Lookup Disabled
A	one-time	1000	5 (first row is an exact match)	5 (first row is an exact match)
B	null	500	10 (second row matches explicit null in input)	10 and 15 (second and third rows match the product and price columns, and null matches all values in the payment type column)
A	null	1000	No output values (first row's 'one-time' doesn't match explicit null)	5 (first row matches the product and price and null matches all payment type values)
B	one-time	500	15 (third row is an exact match)	15 (third row is an exact match)

Null Values vs. Empty Strings in CSV Decision Tables

When you create or edit a decision table by using a CSV file, Business Rules Engine treats empty cells as null. If you add the string "null", it's treated as an invalid value. In case of boolean values, an empty input is treated as false.

Consider a decision table with these CSV rows for the Payment Type column.

Product	Payment Type (cell value in CSV)	How Business Rules Engine Interprets the Value
A	one-time	Treated as the string one-time.
B	(empty cell)	Treated as a null value.
C	null	Treated as an invalid input.

Important If you have existing CSV uploads with empty strings that you didn't intend as null values, overwrite the CSV to reflect intended behavior.