How To Fix SWF_RLS_001121 - Operator '&1': Expressions '&2' and '&3' cannot be compared

SAP Error Message - Details

• Message type: E = Error

• Message class: SWF_RLS_001 - Condition Evaluation and Rule Evaluation

• Message number: 121

• Message text: Operator '&1': Expressions '&2' and '&3' cannot be compared

What causes this issue?

The following expressions refer to values that do not belong to value
categories:
&V2&
&V3&
These categories are:
Objects
Tables
Structures
Elementary values (numbers, character strings, date, time, ...)
In this way, for example, objects that have other objects, but that are
without tables, structures, or elementary values can be compared.

System Response

The condition entered is not syntactically correct in this format.

How to fix this error?

Correct the condition in row &V4& by using comparable data objects as
operands. 'F4 possible entries' are available both when entering
constants and also when entering expressions.

Procedure for System Administrators

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

Error message extract from SAP system. Copyright SAP SE.

Smart SAP Assistant

• What is the cause and solution for SAP error message SWF_RLS_001121 - Operator '&1': Expressions '&2' and '&3' cannot be compared ?

  The SAP error message SWF_RLS_001121 indicates that there is an issue with comparing two expressions in a workflow or rule set. This typically occurs when the data types of the expressions being compared are incompatible. Here’s a breakdown of the cause, potential solutions, and related information:
  Cause
  
  Data Type Mismatch: The most common cause of this error is that the two expressions being compared are of different data types. For example, trying to compare a string with a number or a date with a string can lead to this error.
  Incorrect Configuration: The workflow or rule may be incorrectly configured, leading to invalid comparisons.
  Null Values: If one of the expressions evaluates to a null value, it may cause issues during comparison.
  
  Solution
  
  
  Check Data Types: Review the data types of the expressions involved in the comparison. Ensure that both expressions are of the same type. You may need to convert one of the expressions to match the other’s data type.
  
  Use appropriate conversion functions if necessary (e.g., converting a string to a number).
  
  
  
  Review Workflow/Rule Logic: Go through the logic of the workflow or rule to ensure that the comparisons being made are valid and logical. Make adjustments as needed to ensure that only compatible types are compared.
  
  
  Handle Null Values: Implement checks to handle null values before performing comparisons. This can prevent runtime errors and ensure that comparisons are valid.
  
  
  Debugging: If the issue persists, consider using debugging tools available in SAP to trace the execution of the workflow or rule. This can help identify where the incompatible comparison is occurring.
  
  
  Consult Documentation: Refer to SAP documentation or help resources for specific guidance on the expressions and data types you are working with.
  
  
  Related Information
  
  SAP Notes: Check for any relevant SAP Notes that may address this specific error or provide additional context.
  Community Forums: Engage with SAP community forums or support channels where similar issues may have been discussed.
  Testing: After making changes, thoroughly test the workflow or rule to ensure that the error is resolved and that the logic behaves as expected.
  
  By addressing the data type mismatch and ensuring that the expressions being compared are compatible, you should be able to resolve the SWF_RLS_001121 error.