Joining various tables using FOR ALL ENTRIES - inner-join

Question

I have created a method for fetching data from tables.
My importing parameters are IV_RCP_NO, IV_VERS, IV_ALT and exporting parameter is ET_TABLE.
Now I am using INNER JOIN for joining 4 tables but the requirement says it should be done using FOR ALL ENTRIES clause.
Can someone please help me out to proceed with it?
Here is my code:
SELECT RCP_TBL~SEARCH_TERM PLNT_TBL~PLANT DESCR_TBL~DESCR RCP_STATUS~DESCR
INTO TABLE ET_TABLE
FROM ESTRH AS ESTRH_TBL
INNER JOIN /PLMB/RCP_RECIPE AS RCP_TBL
ON ESTRH_TBL~RECN = RCP_TBL~SUBRECN
INNER JOIN /PLMB/SAM_NODE_T AS RCP_STATUS
ON RCP_STATUS~STATUS_ID = RCP_TBL~STATUS
INNER JOIN /PLMB/RCP_PLNT AS PLNT_TBL
ON RCP_TBL~RCP_GUID = PLNT_TBL~RCP_GUID
INNER JOIN /PLMB/RCP_DESCR AS DESCR_TBL
ON PLNT_TBL~RCP_GUID = DESCR_TBL~OBJECT_GUID
AND RCP_TBL~RCP_GUID = DESCR_TBL~OBJECT_GUID
WHERE SUBID = IV_RCP_NO AND ALT_NO = IV_ALT AND VERS_NO = IV_VERS.

Answer 1

If the join can be done without for all entries then do that. This will yield best performance.
For all entries is a tool to simplify queries where you already have part of the data in an internal table, from some previously executed code or pre-computation. It effectively results in a series of independent selects whose results are merged after individual completion - meaning this results in multiple database roundtrips, which can drastically worsen performance.
If you have specific requirements to apply the for all entries, you should clarify which part of the data is already there and needs to be joined that way. Otherwise any suggestion from StackOverflowers will remain inefficient guesswork.

Answer 2

You can refer the below code-
* Local structure
TYPES: BEGIN OF ty_estrth,
subid TYPE esesubid,
recn TYPE eserecn,
END OF ty_estrth.
* Internal table
DATA: lt_estrh TYPE STANDARD TABLE OF ty_estrth.
SELECT subid recn FROM estrh
INTO TABLE lt_estrh
WHERE subid = iv_rcp_no.
IF lt_estrh IS NOT INITIAL.
SELECT * FROM /plmb/rcp_recipe
INTO TABLE lt_rcp_recipe "Internal table of type /PLMB/RCP_RECIPE
FOR ALL ENTRIES IN lt_estrh
WHERE subrecn = lt_estrh-recn
AND alt_no = iv_alt AND vers_no = iv_vers.
IF lt_rcp_recipe IS NOT INITIAL.
SELECT * FROM /plmb/sam_node_t
INTO TABLE lt_sam_node_t "Internal table of type /PLMB/SAM_NODE_T
FOR ALL ENTRIES IN lt_rcp_recipe
WHERE status_id = lt_rcp_recipe-status.
SELECT * FROM /plmb/rcp_plnt
INTO TABLE lt_rcp_plnt " Internal table of type /PLMB/RCP_PLNT
FOR ALL ENTRIES IN lt_rcp_recipe
WHERE rcp_guid = lt_rcp_recipe-rcp_guid.
SELECT * FROM /plmb/rcp_descr
INTO TABLE lt_rcp_descr " Internal table of type /PLMB/RCP_DESCR
FOR ALL ENTRIES IN lt_rcp_recipe
WHERE rcp_guid = lt_rcp_recipe-rcp_guid.
ENDIF.
ENDIF.
You'll get your data in below internal tables
lt_rcp_recipe
lt_sam_node_t
lt_rcp_plnt
lt_rcp_descr
Better declare a local structure with specific fields which you want to read, as i declared above. After that you have to read and fill data in exporting table ET_TABLE.