What is the link in SAP Business One between Sales Orders, Deliveries, and Invoices

I'm trying to join ORDR, ODLN and OINV in a SAP Business One query, but I can't seem to find a field that they share in common.

There must be some record somewhere that links one to another.

Are they linked via a separate table? Or am I missing something obvious?

I am using SAP HANA as my DB, so queries in HANA are preferred rather than MSSQL.

First, credit to Eralper for their answer, as the link contained in it helped me find the solution I was looking for. However, their solution does not include an explanation and does not quite give the result that is being looked for.

The main information for a Sales Order in SAP is stored in two tables, ORDR and RDR1. ORDR has one line for each Sales Order, while RDR1 has one line for each product row on the Sales Order.

Delivery Notes and Invoices (and basically any document in SAP) follow this pattern.

Why is this important to this question? Because the column that contains the data to link Sales Orders, Delivery Notes and Invoices is in RDR1 (or the similar variant). It's name is TrgetEntry.

As there is a row for each product on a Sales Order, we can't simply do a join, as any Sales Order that has more than one product will appear multiple times in the result. The following query uses grouping to show a table that has a line for each Sales Order, and has the needed information to link it to Delivery Notes.

SELECT T0."DocEntry" AS "SO DE", T0."DocNum" AS "Sales Order Number", T1."TrgetEntry" AS "SO TE", COUNT(T0."DocNum") AS "Rows"
FROM ORDR T0
LEFT JOIN RDR1 T1 ON T0."DocEntry" = T1."DocEntry"
GROUP BY T0."DocEntry", T0."DocNum", T1."TrgetEntry"

By just changing the table names, similar queries can be created for Delivery Notes and Invoices.

Then you can use the TrgetEntry and DocEntry to link the various results.

The final code I use to show Sales Orders, their related Deliveries and Invoices is the following:

SELECT S0."SalesOrderNumber", S1."DeliveryNumber", S2."DocNum" AS "InvoiceNumber", S0."Rows", S2."DocTotal"
FROM (SELECT T0."DocEntry" AS "SO_DE", T0."DocNum" AS "SalesOrderNumber", T1."TrgetEntry" AS "SO_TE", COUNT(T0."DocNum") AS "Rows"
FROM ORDR T0
LEFT JOIN RDR1 T1 ON T0."DocEntry" = T1."DocEntry"
GROUP BY T0."DocEntry", T0."DocNum", T1."TrgetEntry") S0
LEFT JOIN (SELECT T0."DocEntry" AS "DN_DE", T0."DocNum" AS "DeliveryNumber", T1."TrgetEntry" AS "DN_TE"
FROM ODLN T0
LEFT JOIN DLN1 T1 ON T0."DocEntry" = T1."DocEntry"
GROUP BY T0."DocEntry", T0."DocNum", T1."TrgetEntry") S1 ON S0."SO_TE" = S1."DN_DE"
LEFT JOIN OINV S2 ON S1."DN_TE" = S2."DocEntry"

Please check https://archive.sap.com/discussions/thread/1440163 There following relationship is given

 SELECT Distinct(T0.DocNum ),T0.DocDate, T0.CardCode, T0.CardName, T1.ItemCode, T1.Quantity, T1.Price,T1.TotalSumSy, T0.DocTotal
    FROM ORDR T0 
    INNER JOIN RDR1 T1 ON T0.DocEntry = T1.DocEntry 
    INNER JOIN ODLN T2 ON T2.DocEntry = T1.TrgetEntry
    INNER JOIN DLN1 T3 on T3.DocEntry = T2.Docentry
    INNER JOIN OINV T4 ON T4.DocEntry = T3.TrgetEntry
    INNER JOIN INV1 T5 ON T5.DocEntry = T4.DocEntry
    LEFT JOIN ORDN T6 ON T6.DocEntry = T5.TrgetEntry
    LEFT JOIN RDN1 T7 ON T7.DocEntry = T6.DocEntry

So following relation is also true

SELECT *
FROM ODLN T2 
INNER JOIN DLN1 T3 on T3.DocEntry = T2.Docentry
INNER JOIN OINV T4 ON T4.DocEntry = T3.TrgetEntry