This is a default command (e.g. WBSP page with no configuration section or with no WB_Command value will execute RENDER command). When executed, it processes all WhizBase tags and functions that exist in the page. If database related variables are defined, this command will open the recordset, but it will display only first record of the recordset.
Important: If your WBSP page displays only one record, and you are positive that there is more records in recordset, and that you have placed <!--WB_BeginDetail--> and <!--WB_EndDetail--> properly, then it is very possible that you have forgot to set WB_Command properly (to Q, P or L) and that your WBSP page executes RENDER command.