Multiple formats in PF or LF

I'm starting to think that I am searching for something that doesn't exist.



I thought there was a way of having a single "flat file" and breaking it
into multiple record formats in the DDS so the individual records could be
accessed via SQL



For example: a flat file that would contain sales data



HdrFmt

RcdType

SaleNumber

SaleDate



DtlFmt

RcdType

SaleNumber

Item

Quantity

Price



PayFmt

RcdType

SaleNumber

PaymentType

Amount



If I wanted to query all of the detail records to find out what items were
sold, I could do something like select item, count(*) from flatfile where
rcdtype = 'DTL' group by item



Am I just thoroughly confused thinking I have seen something like this in
the past? If not, can someone please provide the DDS to show me how it is
done? Nothing that I have tried has worked. I know I can create separate
PFs and copy the appropriate data to each file via a CPYF *NOCHK selecting
the appropriate rcdtype but that defeats the purpose of what I am trying to
do.