Parallel Cursor To Improve Your ABAP Program Performance

Parallel Cursor To Improve Your ABAP Program Performance

Parallel cursor is a technique used in ABAP to enhance the performance of programs, especially when dealing with nested loops

Here’s how it helps:

1.Reduces Full Table Scans: In conventional ABAP, using the LOOP statement with the WHERE clause scans the entire table to find matching key fields. This scanning happens for each row in the outer loop, leading to a high processing time. Parallel cursor helps avoid this by using the READ TABLE statement with BINARY SEARCH to quickly find if an entry exists in the inner table.

2.Optimizes Nested Loops: If you use nested loops or nested selects in your program, it can lead to performance degradation. Parallel cursor technique can be used to increase the performance of the program when there are nested loops.

here is a ready-to-use example of a parallel cursor in ABAP:

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22

DATA: itab TYPE TABLE OF ty_but000, itab1 TYPE TABLE OF ty_but050, v_tabix TYPE sy-tabix. " Assume itab and itab1 are filled with data SORT itab BY field1. SORT itab1 BY field1. LOOP AT itab INTO DATA(wa). READ TABLE itab1 INTO DATA(wa1) WITH KEY field1 = wa-field1 BINARY SEARCH. v_tabix = sy-tabix. IF sy-subrc EQ 0. LOOP AT itab1 INTO wa1 FROM v_tabix. IF wa1-field1 NE wa-field1. EXIT. ENDIF. " It will loop from that index ENDLOOP. ENDIF. ENDLOOP.

In this example, itab and itab1 are internal tables, and wa and wa1 are work areas for these tables. The READ TABLE statement is used to find the first occurrence of a record in itab1 that matches a record in itab. 

If a match is found, the system field sy-subrc is set to 0, and the index of the matching record is stored in v_tabix. The inner loop then processes all matching records in itab1 starting from the stored index. The inner loop will exit when it encounters a record in itab1 that doesn’t match the current record in itab. This ensures that only matching records are processed. 

Please replace ty_but000 and ty_but050 with your actual table types, and field1 with the actual field you want to compare. Also, ensure that itab and itab1 are sorted by the field you want to compare before the loop. 

Remember, the tables should be sorted by the same key field before using parallel cursor. Also, it’s important to exit the inner loop when keys don’t match to ensure that only matching records are processed.

Tags: 

1) How To Improve ABAP program performance using Parallel cusrsor

2) Example program for Parallel cursor technique