How To Fix FDT_EXPRESSIONS135 - Decision table is too complex for completeness check

SAP Error Message - Details

• Message type: E = Error

• Message class: FDT_EXPRESSIONS - Formula & Derivation Tool: Expressions

• Message number: 135

• Message text: Decision table is too complex for completeness check

What causes this issue?

The system has tried to carry out a check in order to find out whether
the supplied conditions in a decision table are sufficient to cover all
foreseeable occurrences of the business transaction affected by the
given condition parameters. However, for technical reasons it is
impossible for the check to yield a reliable result.
INCLUDE FDT_CHECK_FAIL_REASON OBJECT DOKU ID TX

System Response

The system issues an error message and will not allow you to continue with this transaction until the error is resolved.

How to fix this error?

We recommend you have a thorough look at the decision table data and do
some testing to make sure that all use cases that you expect during
productive use are covered by the table data.
If it is crucial that you can present a positive check result, maybe a
redesign of the decision table might help with nested expressions
replaced by constants or ranges.

Procedure for System Administrators

Error message extract from SAP system. Copyright SAP SE.

Smart SAP Assistant

• What is the cause and solution for SAP error message FDT_EXPRESSIONS135 - Decision table is too complex for completeness check ?

  The SAP error message FDT_EXPRESSIONS135 indicates that a decision table is too complex for the system to perform a completeness check. This typically occurs in the context of SAP's Business Rules Framework (BRF+) or similar decision-making tools where decision tables are used to define business logic.
  Cause:
  
  Complexity of Decision Table: The decision table may have too many conditions, rules, or combinations of inputs that exceed the system's capability to evaluate for completeness.
  High Number of Conditions: If the decision table has a large number of conditions or outcomes, it can lead to a combinatorial explosion, making it difficult for the system to ensure that all possible scenarios are covered.
  Performance Limitations: The system may have internal limits on the complexity of decision tables to maintain performance and avoid excessive resource consumption.
  
  Solution:
  
  
  Simplify the Decision Table:
  
  Reduce the Number of Conditions: Try to minimize the number of conditions or rules in the decision table. This can be done by consolidating similar rules or removing unnecessary ones.
  Break Down Complex Tables: If possible, break the decision table into smaller, more manageable tables that can be checked for completeness individually.
  Use Hierarchical Structures: Consider using hierarchical decision-making structures where simpler decision tables are used to handle specific cases.
  
  
  
  Review Logic: Ensure that the logic defined in the decision table is necessary and that there are no redundant or overlapping rules.
  
  
  Consult Documentation: Check SAP documentation or notes related to BRF+ or decision tables for any specific guidelines or limitations regarding complexity.
  
  
  Performance Tuning: If applicable, consult with your SAP Basis team to see if there are any performance tuning options available for your system that might help with processing complex decision tables.
  
  
  Contact SAP Support: If the issue persists and you cannot simplify the decision table further, consider reaching out to SAP support for assistance. They may provide insights or patches that can help with the issue.
  
  
  Related Information:
  
  SAP Notes: Look for SAP Notes related to BRF+ and decision tables for any known issues or updates that might address this error.
  BRF+ Documentation: Review the official SAP documentation for BRF+ to understand best practices for designing decision tables and managing complexity.
  Community Forums: Engage with SAP community forums or user groups where similar issues may have been discussed, and solutions shared.
  
  By addressing the complexity of the decision table and following the suggested solutions, you should be able to resolve the FDT_EXPRESSIONS135 error.