Last Modified Date: 06 Jul 2018
EnvironmentTableau Prep 2018.1
ResolutionAs a workaround, replace any join key field containing nulls with a calculated field using one of the functions for null handling in Tableau.
If the join key is a string:
IFNULL([join key], '')will replace null values with empty strings.
If the join key is a number:
will replace null values with zeroes.
CauseIn a relational database, a null is not a value, a null is the absence of a value.
Because of this, two nulls are not treated as logically equivalent, and null join key values are ignored.
Additional InformationNulls Handling - String, Date, Numerical Data types
Null (SQL) at Wikipedia
Thank you for providing your feedback on the effectiveness of the article.
Open new Case
Training and Tutorials