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Inverse Reads on Internal Table with FOR

This example demonstrates how sequential inverse reads are performed on an internal table.

Other versions: 7.31 | 7.40 | 7.54

Source Code

    DATA
      itab TYPE STANDARD TABLE OF i
           WITH EMPTY KEY
           WITH NON-UNIQUE SORTED KEY sort_key COMPONENTS table_line.

    itab = VALUE #( ( 2 ) ( 5 ) ( 1 ) ( 3 ) ( 4 ) ).

    DATA(output) =
      REDUCE string(
        INIT o = ``
        FOR  i = lines( itab ) THEN i - 1 WHILE i > 0
        NEXT o = o && COND #( LET r = itab[ KEY sort_key INDEX i ] IN
                             WHEN r > 2 THEN r && ` ` ) ).

    cl_demo_output=>display( output ).

Description

In a conditional iteration, an internal table is read using WHILE and a table expression. The table expression uses the secondary table key sort_key and the result is created in a conditional expression using cond. The example shows how to bypass the restriction that inverse table iterations cannot be performed.