How To Fix MC759 - Join for field &-& uses an SY field

SAP Error Message - Details

• Message type: E = Error

• Message class: MC - Aggregate: views, matchcodes, lock objects

• Message number: 759

• Message text: Join for field &-& uses an SY field

What causes this issue?

A join condition on a field of the system table SY (or SYST) was
defined. This is not permitted for database views because the system
table is not known to the database.

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?

Error message extract from SAP system. Copyright SAP SE.

Smart SAP Assistant

• What is the cause and solution for SAP error message MC759 - Join for field &-& uses an SY field ?

  The SAP error message MC759, which states "Join for field &-& uses an SY field," typically occurs in the context of SAP's reporting and data extraction processes, particularly when working with InfoObjects in the SAP BW (Business Warehouse) environment. This error indicates that there is an issue with the way fields are being joined in a query or report, specifically that a field from the SY (system) table is being used in a join condition, which is not allowed.
  Cause:
  
  Improper Join Conditions: The error usually arises when a query or report attempts to join fields from different tables, and one of those fields is from a system table (SY) that is not compatible with the other fields being joined.
  Field Mismatch: The fields being joined may not have a logical relationship or may not be of compatible data types.
  Query Design Issues: The design of the query or the data model may not adhere to the best practices for joining tables in SAP BW.
  
  Solution:
  
  Review Join Conditions: Check the join conditions in your query or report. Ensure that you are not trying to join a field from the SY table with fields from other tables. If necessary, remove or replace the SY field with a compatible field.
  Modify Query Design: If the query design is causing the issue, consider redesigning the query to avoid using SY fields in joins. This may involve using different fields or restructuring the data model.
  Data Type Compatibility: Ensure that the fields being joined are of compatible data types. If they are not, you may need to convert them or use a different field that matches the data type.
  Consult Documentation: Refer to SAP documentation or help resources for guidance on proper join practices and the use of SY fields in queries.
  
  Related Information:
  
  SAP Notes: Check for any relevant SAP Notes that may address this specific error or provide additional guidance on resolving it.
  SAP Community: Engage with the SAP Community forums to see if other users have encountered similar issues and what solutions they have found.
  Training and Best Practices: Consider training on SAP BW query design and best practices for data modeling to avoid similar issues in the future.
  
  If the problem persists after trying these solutions, it may be beneficial to consult with an SAP BW expert or your organization's SAP support team for further assistance.