Address subselect field in the onRecord event

Hello,

I have a simple question for subselect fields in report PDF. I have fields which are displayed in the left menu with positionen.CASN_ID, positionen.CASN_CSTA,etc

IN the onRecord event I want to make an select using one of these fields. But when I run this I get an error: array to string conversion.
The select is as following:
$sql=“SELECT SNRP_ID,SNRP_CASN_ID, SNRP_REP_ID FROM TB_Seriennummer_ReparaturGrund WHERE SNRP_CASN_ID=”.{positionen.CASN_ID};

The question is how to address correctly the field positionen.CASN_ID.

Thank you for your help!

If it’s a detail, you must specifify <detailName>.positionen.CASN_ID

If you show us your query and/or an screenshot can help.