How To Fix RS_HCPR_MODEL030 - Temporal join: Left outer chains are not allowed (&1)

SAP Error Message - Details

• Message type: E = Error

• Message class: RS_HCPR_MODEL - Messages related to the HANA Composite Provider Backend

• Message number: 030

• Message text: Temporal join: Left outer chains are not allowed (&1)

What causes this issue?

The CompositeProvider consists of at least two left outer joined
PartProviders. The join partners of one of these left outer joined
PartProviders belong to another left outer joined PartProvider. This is
not allowed.
The join partners of a left outer joined PartProvider must belong to an
inner joined PartProvider.

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 RS_HCPR_MODEL030 - Temporal join: Left outer chains are not allowed (&1) ?

  The SAP error message RS_HCPR_MODEL030, which states "Temporal join: Left outer chains are not allowed (&1)," typically occurs in the context of SAP HANA or SAP BW when working with data models that involve temporal joins. This error indicates that there is an issue with the way the temporal join is defined in your data model.
  Cause:
  The error arises when you attempt to create a temporal join that includes a left outer join in a chain of joins. In SAP HANA, temporal joins are used to combine data from different time periods, but they have specific requirements regarding the types of joins that can be used. Specifically, left outer joins are not permitted in a chain of temporal joins because they can lead to ambiguous results and inconsistencies in the temporal data.
  Solution:
  To resolve this error, you can take the following steps:
  
  
  Review the Join Logic: Examine the data model and the specific joins that are being used. Identify where the left outer join is being applied in the context of the temporal join.
  
  
  Change the Join Type: If possible, change the left outer join to an inner join or a right outer join, depending on your data requirements. This change should help you avoid the error while still achieving the desired results.
  
  
  Simplify the Join Chain: If the join chain is complex, consider breaking it down into simpler components. You may need to create intermediate views or tables that can be joined without violating the temporal join rules.
  
  
  Consult Documentation: Refer to the SAP HANA or SAP BW documentation for guidelines on temporal joins and the types of joins that are allowed. This can provide additional insights into best practices and limitations.
  
  
  Test the Model: After making changes, test the data model to ensure that it functions correctly and that the error no longer occurs.
  
  
  Related Information:
  
  Temporal Joins: These are used to combine data based on time dimensions, allowing you to analyze data across different time periods.
  Join Types: Understanding the differences between inner joins, left outer joins, and right outer joins is crucial for designing effective data models.
  SAP HANA Documentation: The official SAP documentation provides detailed information on data modeling, including best practices for using temporal joins and other advanced features.
  
  If you continue to experience issues after trying these solutions, consider reaching out to SAP support or consulting with a data modeling expert who has experience with SAP HANA or BW.