1228341 - Database Connector Error: 'If tables are already linked then the join type cannot change' when refreshing a report in Crystal Reports

• Error when refreshing a report.
• After changing table linking between two tables, it fails to refresh.
• In Crystal Reports, when refreshing a report, it fails with the error: 
    
  "Error: Failed to retrieve data from the database.
   Database Connector Error: 'If tables are already linked then the join type cannot change' "

• Crystal Reports XI
• Crystal Reports XI R2
• SAP Crystal Reports 2008 
• SAP Crystal Reports 2011

1. In Crystal Reports, open a report.
2. In the Database Expert, add tables to the report, or modify the links between tables.
3. When refreshing the report, it fails with the error:  
       
   "Database Connector Error: 'If tables are already linked then the join type cannot change' "

• Limitation of the query engine caused by the requirement of having multiple links between two tables.
• By design, the linking between the tables needs to be using the same join type.

• The solution is to link the tables using the same join type.
      
• Workarounds:
• Use a View, where are the links are done on your database side; or
• Use a Stored Procedure; or
• Use 'Add Command'. This option allows you to write your own SQL Query. 

CR , KBA , BI-RA-CR , Crystal Reports designer or Business View Manager , Problem

Crystal Reports 2008 V0 ; SAP Crystal Reports 2011 ; SAP Crystal Reports XI ; SAP Crystal Reports XI R2