带有内连接的 Select 语句需要永远

Question

(....)
DATA: BEGIN OF g00 OCCURS 100,
            werks LIKE lqua-werks,
            lgort LIKE lqua-lgort,
            matnr LIKE lqua-matnr,
            charg LIKE lqua-charg,
            maktx LIKE makt-maktx,
            verme LIKE lqua-verme,
            meins LIKE lqua-meins,
            dispo LIKE marc-dispo,
      END OF g00.
(.....)
 CLEAR : g00.
  REFRESH : g00.
  SELECT lqua~bestq lqua~charg lqua~lgort lqua~lgnum lqua~lgpla
lqua~lgtyp lqua~matnr lqua~meins lqua~verme lqua~werks makt~maktx
         makt~matnr makt~spras mara~bismt mara~matnr marc~dispo
         marc~matnr marc~werks
  INTO (lqua-bestq , lqua-charg , lqua-lgort , lqua-lgnum , lqua-lgpla ,
 lqua-lgtyp , lqua-matnr , lqua-meins , lqua-verme , lqua-werks ,
makt-maktx , makt-matnr , makt-spras , mara-bismt , mara-matnr ,
marc-dispo , marc-matnr , marc-werks )
  FROM ( lqua
         INNER JOIN makt
         ON makt~matnr = lqua~matnr
         INNER JOIN mara
         ON mara~matnr = makt~matnr
         INNER JOIN marc
         ON marc~werks = lqua~werks
         AND marc~matnr = lqua~matnr )
         WHERE lqua~bestq IN sbestq
           AND lqua~lgnum IN slgnum
           AND lqua~lgpla IN slgpla
           AND lqua~lgtyp IN slgtyp
           AND lqua~matnr IN smatnr
           AND lqua~werks IN swerks
           AND makt~maktx IN smaktx
           AND makt~spras IN sspras
*           AND MARA~BISMT IN Sbismt
           AND marc~dispo IN sdispo.
    MOVE-CORRESPONDING mara TO g00.
    MOVE-CORRESPONDING makt TO g00.
    MOVE-CORRESPONDING marc TO g00.
    MOVE-CORRESPONDING lqua TO g00.
    COLLECT g00.
  ENDSELECT.

Can anyone help to improve the performance of code above.

Answer 1

Your starting table for the join (LQUA) is not selecting on key or indexed fields, which will always run slower than if you are able to use them.

While there doesn't appear to be a way to join everything on key fields, you might have better luck if you tweak the query to initially pull from MARA (where MATNR is a key field):

FROM ( mara
         INNER JOIN makt
         ON makt~matnr = mara~matnr
         INNER JOIN lqua
         ON lqua~matnr = mara~matnr
         INNER JOIN marc
         ON marc~werks = mara~werks
         AND marc~matnr = mara~matnr )...

Answer 2

DO NOT use SELECT END SELECT in the scenario you have described below. Try doing the following :

-> Create a local type with the fields you are picking up select ( lt_yourtype)

( lqua~bestq lqua~charg lqua~lgort lqua~lgnum lqua~lgpla lqua~lgtyp lqua~matnr lqua~meins lqua~verme lqua~werks makt~maktx makt~matnr makt~spras mara~bismt mara~matnr marc~dispo marc~matnr marc~werks )

-> Create work area ( prefer field symbol ) and internal table of the above local type ( lt_yourtype )

-> Replace the given select with :

select lqua~bestq lqua~charg lqua~lgort lqua~lgnum lqua~lgpla lqua~lgtyp lqua~matnr lqua~meins lqua~verme lqua~werks makt~maktx makt~matnr makt~spras mara~bismt mara~matnr marc~dispo marc~matnr marc~werks into table lt_yourtype FROM ( lqua INNER JOIN makt ON makt~matnr = lqua~matnr INNER JOIN mara ON mara~matnr = makt~matnr INNER JOIN marc ON marc~werks = lqua~werks AND marc~matnr = lqua~matnr ) WHERE lqua~bestq IN sbestq AND lqua~lgnum IN slgnum AND lqua~lgpla IN slgpla AND lqua~lgtyp IN slgtyp AND lqua~matnr IN smatnr AND lqua~werks IN swerks AND makt~maktx IN smaktx AND makt~spras IN sspras * AND MARA~BISMT IN Sbismt AND marc~dispo IN sdispo.

loop into lt_yourtype assigning .

*move data to the correct structure and fields here

endloop.