ABAP Select data from SAP table LAGPL into internal table

Get Example source ABAP code based on a different SAP table
  Get ABAP code

Below is a number of ABAP code snippets to demonstrate how to select data from SAP LAGPL table and store it within an internal table, including using the newer @DATA inline declaration methods. It also shows you various ways to process this data using ABAP work area, inline declaration or field symbols including executing all the relevant CONVERSION_EXIT routines specific to LAGPL. See here for more generic Select statement tips.

Sometimes data within SAP is stored within the database table in a different format to what it is displayed to the user. These input/output conversation FM routines are what translates the data between the two formats.

There is also a full declaration of the LAGPL table where each field has a char/string type for you to simply copy and paste. This allows you to use processing that is only available to these field types such as the CONCATENATE statement.

DATA: IT_LAGPL TYPE STANDARD TABLE OF LAGPL,
      WA_LAGPL TYPE LAGPL,
      GD_STR TYPE STRING.

DATA: lo_typedescr type REF TO cl_abap_typedescr.
DATA: lv_fieldname type fieldname.

FIELD-SYMBOLS: <FIELD> TYPE any.
FIELD-SYMBOLS: <LAGPL> TYPE LAGPL.

*Process all fields in table header/work area as string values
  PERFORM process_as_string_field_values CHANGING wa_LAGPL.

SELECT *
*restrict ABAP select to first 10 rows
 UP TO 10 ROWS      
  FROM LAGPL
  INTO TABLE IT_LAGPL.

*Select data and declare internal table using in-line method @DATA
*SELECT *
*  FROM LAGPL
*  INTO TABLE @DATA(IT_LAGPL2).
*--Further methods of using ABAP code to  select data from SAP database tables

*You can also declare the header/work area using the in-line DATA declaration method
READ TABLE IT_LAGPL INDEX 1 INTO DATA(WA_LAGPL2).


*Demonstrate how to loop at an internal table and update values using a FIELD-SYMBOL
LOOP AT IT_LAGPL ASSIGNING <LAGPL>.

*To update a field value using a field symbol simply change the value via the field symbol pointer
<LAGPL>-MANDT = 1.
<LAGPL>-LGNUM = 1.
<LAGPL>-LGTYP = 1.
<LAGPL>-LGPLA = 1.
<LAGPL>-LGBER = 1.

ENDLOOP.

LOOP AT IT_LAGPL INTO WA_LAGPL.
*Write horizonal line to screen report.
  WRITE:/ sy-uline.

*Write selected data to screen/report before conversion.
  WRITE:/ sy-vline,   WA_LAGPL-LPTYP, sy-vline,
  WA_LAGPL-PLAUF, sy-vline,
  WA_LAGPL-SKZUE, sy-vline,
  WA_LAGPL-SKZSI, sy-vline,
  WA_LAGPL-KZLER, sy-vline,
  WA_LAGPL-KZVOL, sy-vline.
ENDLOOP.
   
*Add any further fields from structure WA_LAGPL you want to display...

  WRITE:/ sy-uline.
* Aternatively use generic code to Write field values (and NAME) to screen report
  DO.
    ASSIGN COMPONENT sy-index OF STRUCTURE wa_LAGPL TO <field>.
    IF sy-subrc <> 0. EXIT. ENDIF.
    WRITE:/ 'Field Value', <field>, sy-vline.
    gd_str = <field> .
    lo_typedescr ?= CL_ABAP_DATADESCR=>DESCRIBE_BY_DATA( <field> ).
    lv_fieldname = lo_typedescr->GET_RELATIVE_NAME( ).
    WRITE:/ 'Field Name', lv_fieldname.
  ENDDO.

  
*Redo loop but convert all fields from internal to out value  
LOOP AT IT_LAGPL INTO WA_LAGPL.


*Write horizonal line to screen report.
  WRITE:/ sy-uline.

*Convert all fields to display/output versions using conversion routines
  PERFORM convert_all_field_values CHANGING wa_EKKO.
	 
ENDLOOP.

  
*&---------------------------------------------------------------------*
*& Form convert_all_field_values
*&---------------------------------------------------------------------*
FORM convert_all_field_values CHANGING p_EKKO LIKE wa_EKKO.
DATA: ld_input(1000) TYPE c, ld_output(1000) TYPE C.
ENDFORM. 

*&---------------------------------------------------------------------*
*& Form process_as_string_field_values
*&---------------------------------------------------------------------*
FORM process_as_string_field_values CHANGING p_EKKO LIKE wa_EKKO.

TYPES: BEGIN OF T_LAGPL_STR, 
MANDT TYPE STRING,
LGNUM TYPE STRING,
LGTYP TYPE STRING,
LGPLA TYPE STRING,
LGBER TYPE STRING,
LPTYP TYPE STRING,
PLAUF TYPE STRING,
SKZUE TYPE STRING,
SKZSI TYPE STRING,
KZLER TYPE STRING,
KZVOL TYPE STRING,
SORLP TYPE STRING,
RKAPV TYPE STRING,END OF T_EKKO_STR.
DATA: WA_LAGPL_STR type T_EKKO_STR.

DATA: ld_text TYPE string.

LOOP AT IT_EKKO INTO WA_EKKO.
  MOVE-CORRESPONDING wa_EKKO TO WA_EKKO_STR.
  CONCATENATE: sy-vline
WA_LAGPL_STR-MANDT sy-vline 
WA_LAGPL_STR-LGNUM sy-vline 
WA_LAGPL_STR-LGTYP sy-vline 
WA_LAGPL_STR-LGPLA sy-vline 
WA_LAGPL_STR-LGBER sy-vline 
WA_LAGPL_STR-LPTYP sy-vline 
WA_LAGPL_STR-PLAUF sy-vline 
WA_LAGPL_STR-SKZUE sy-vline 
WA_LAGPL_STR-SKZSI sy-vline 
WA_LAGPL_STR-KZLER sy-vline 
WA_LAGPL_STR-KZVOL sy-vline 
WA_LAGPL_STR-SORLP sy-vline 
WA_LAGPL_STR-RKAPV sy-vline      INTO ld_text SEPARATED BY SPACE.

*Add any further fields from structure WA_EKKO_STR you want to CONCATENATE...
ENDLOOP.
ENDFORM.