来自内部表的动态查询

Question

我有一个需要动态运行此查询的需求。有没有人有过这种查询？

READ TABLE table_name TRANSPORTING feild_name INTO table_name 
       WITH KEY key_feild1 = value1, 
         key_feild2 = value2, 
         key_feild3 = value3. 

Answer 1

根据this answer，下面是另一种可能的解决方案。虽然，它有点难看，但它确实有效。

DATA: table_tab TYPE TABLE OF rsdstabs, 
     selid  TYPE rsdynsel-selid, 
     cond_tab TYPE rsds_twhere, 
     field_tab TYPE TABLE OF rsdsfields, 
     string TYPE string. 
FIELD-SYMBOLS <cond> LIKE LINE OF cond_tab. 

table_tab = VALUE #((prim_tab = 'USR02')). 

CALL FUNCTION 'FREE_SELECTIONS_INIT' 
    EXPORTING 
    kind   = 'T' 
    IMPORTING 
    selection_id = selid 
    TABLES 
    tables_tab = table_tab 
    EXCEPTIONS 
    OTHERS  = 4. 
IF sy-subrc <> 0. 
    MESSAGE 'Error in initialization' TYPE 'I' DISPLAY LIKE 'E'. 
    LEAVE PROGRAM. 
ENDIF. 

CALL FUNCTION 'FREE_SELECTIONS_DIALOG' 
    EXPORTING 
    selection_id = selid 
    title   = 'Free Selection' 
    as_window  = ' ' 
    IMPORTING 
    where_clauses = cond_tab 
    TABLES 
    fields_tab = field_tab 
    EXCEPTIONS 
    OTHERS  = 4. 
IF sy-subrc <> 0. 
    MESSAGE 'No free selection created' TYPE 'I'. 
    LEAVE PROGRAM. 
ENDIF. 

FIELD-SYMBOLS: <fld> TYPE any. 
DATA: field1 TYPE c LENGTH 10, value1 TYPE string, 
     field2 TYPE c LENGTH 10, value2 TYPE string, 
     field3 TYPE c LENGTH 10, value3 TYPE string, 
     field4 TYPE c LENGTH 10, value4 TYPE string, 
     field5 TYPE c LENGTH 10, value5 TYPE string, 
     field6 TYPE c LENGTH 10, value6 TYPE string, 
     field7 TYPE c LENGTH 10, value7 TYPE string, 
     field8 TYPE c LENGTH 10, value8 TYPE string, 
     field9 TYPE c LENGTH 10, value9 TYPE string, 
     num1(1) TYPE n, 
     fldname TYPE fieldname, 
     valname TYPE fieldname. 

ASSIGN cond_tab[ tablename = 'USR02' ] TO <cond>. 

IF sy-subrc = 0. 
    LOOP AT <cond>-where_tab ASSIGNING FIELD-SYMBOL(<fs_cond>). 
    num1 = sy-tabix. 
    CONCATENATE 'field' num1 INTO fldname. 
    CONCATENATE 'value' num1 INTO valname. 
    ASSIGN (fldname) TO <fld>. "assigning field name 
    string = <fs_cond>. 
    REPLACE REGEX `(^.*\(\s)(.*)(EQ.*)` IN string WITH '$2'. 
    <fld> = string. 
    ASSIGN (valname) TO <fld>. "assigning value 
    string = <fs_cond>. 
    REPLACE REGEX `(.*EQ\s)'(.*)('\s*\))` IN string WITH '$2'. 
    <fld> = string. 
    ENDLOOP. 
ENDIF. 

SELECT * 
    FROM usr02 
INTO TABLE @DATA(lt_usr). 

READ TABLE lt_usr ASSIGNING FIELD-SYMBOL(<fs_usr>) 
WITH KEY (field1) = value1 
      (field2) = value2 
      (field3) = value3 
      (field4) = value4 
      (field5) = value5 
      (field6) = value6 
      (field7) = value7 
      (field8) = value8 
      (field9) = value9. 

样本建立在USR02表上。

1. 首先，在动态选择屏幕上，我们指定必要的选择字段（READ TABLE的键）及其值。
   
2. 然后FREE_SELECTIONS_INIT FM根据这些字段建立WHERE条件。
   
3. 我们解析这个条件并获取填充的字段名称和值。
   
4. 在READ TABLE语句模板中，空白字段仅被忽略，表格仅通过填充键读取。
   

Answer 2

READ TABLE指定次级键（here）和关键部件（here）时，但在有限的方式具有动态语法。

我认为LOOP AT是您正在查找的命令。有关使用的更多细节和示例here。看第4部分：

动态WHERE条件cond_syntax可以被指定为一个 字符类数据对象或标准表具有字符状行 类型

哑代码：

LOOP AT table INTO line WHERE (condition). 
    EXIT. --> Exit at first found line. 
ENDLOOP. 
IF sy-subrc = 0. 
... 
ENDIF.