Main report and subreport have the same parameters (date and string) and the same grouping structure (Grouped by Club ID).
What is the best way to link subreport? Linking parameters of report fields?
If there is no grouping by filed and if it is range parameters then the best way is to link parameter of the main report to the relevant parameter in the subreport (e.g Start Date to Start Date) to prevent some missing subreport data.
But if there is a groping and the subreport is in group footer then it is better to link group field (Club ID) to the relevant subreport field to prevent duplication of data in the subreport. Although there could be a case when there is no data for some group field values (Club IDs) in the main report, so there will be no subreport for those values (even if there is a data in the datasource)
Have tested the solution with customer and confirmed that question has been answered.
KBA , BI-RA-CR , Crystal Reports designer or Business View Manager , How To