Selection to join the tables VBFA and VBRK - abap

Question

I have done a selection of the table VBFA, that has selected various SD documents based on the code below, and another selection of the table VBRK that has selected the documents that do not have a NETWR = 0. What I want to achieve is to select only those SD documents that are NETWR NE 0.
The code for the selection of the table VBFA is as follows:
SELECT * FROM vbfa AS v INTO TABLE gt_vbfa_inv
FOR ALL ENTRIES IN gt_vbak
WHERE vbelv = gt_vbak-vbeln
AND vbtyp_n IN ('M', 'O', 'P', '5', '6')
AND stufe = '00'
AND NOT EXISTS ( SELECT * FROM vbfa
WHERE vbelv = v~vbeln
AND posnv = v~posnn
AND vbtyp_n IN ('N', 'S')
AND stufe = '00' ) .
And the code for the selection of the VBRK table is as follows:
IF sy-subrc = 0.
SELECT DISTINCT * FROM vbrk
INTO TABLE gt_vbrk
FOR ALL ENTRIES IN gt_vbfa_inv
WHERE vbeln EQ gt_vbfa_inv-vbeln
AND netwr NE 0.
ENDIF.
Is there any way to merge these to two selection via a new Select or a Loop condition, that will select the documents of the table VBFA, where the documents will not have a NETWR = 0 (or NETWR NE 0)?
Thank you all in advance!

Answer 1

My standard approach for converting code using FOR ALL ENTRIES to a JOIN is this.
Convert it to the new SQL syntax with # in front of every variable.
Replace the SELECT * with the fields I actually need. This is important, because JOINs between two tables will always have duplicate field. So SELECT * doesn't work. And it's a bad practice anyway. You almost never need all the fields, so SELECT * is almost always a waste of memory and CPU cycles.
Take both SELECTs and prefix every column name with the table. For example AND stufe = '00' becomes AND vbfa~stufe = '00'
Take the FOR ALL ENTRIES from the second and turn it into a JOIN-condition on the first select. So
FROM vbrk
FOR ALL ENTRIES IN #gt_vbfa_inv
WHERE vbrk~vbeln = #gt_vbfa_inv-vbeln
AND vbrk~netwr <> 0.
becomes
JOIN vbrk
ON vbrk~vbeln = vbfa~vbeln AND
vbrk~netwr <> 0.
Use an inline data declaration for the result-set. That way you don't need to manually create a table- and structure type for holding the results. The end-result would thus look something like this (untested code):
SELECT vbfa~somefield1
vbfa~somefield2
vbfa~somefield3
vbrk~somefield1
vbrk~somefield2
FROM vbfa
JOIN vbrk ON
vbrk~vbeln = vbfa~vbeln AND
vbrk~netwr NE 0.
INTO TABLE #DATA(gt_results)
FOR ALL ENTRIES IN #gt_vbak
WHERE vbfa~vbelv = gt_vbak-vbeln
AND vbfa~vbtyp_n IN ('M', 'O', 'P', '5', '6')
AND vbfa~stufe = '00'
AND NOT EXISTS ( SELECT * FROM vbfa AS vbfa2
WHERE vbfa2~vbelv = vbfa~vbeln
AND vbfa2~posnv = vbfa~posnn
AND vbfa2~vbtyp_n IN ('N', 'S')
AND vbfa2~stufe = '00' ) .
By the way: If gt_vbak comes from a SELECT too, then you likely can integrate this as another join here, too.