How to select a single value from a table dynamica...

former_member249594 · ‎09-19-2007

Hi experts,

I have an internal table which is combined by two fields:

data: begin of itab occurs 0,

tabname like dd03l-tabname,

tabkey(100) type c,

end of itab.

that is to say, when I loop the itab then I know the database table name and its tablekey value. My requirement is I want to get a single record by the itab-tabkey from the database table itab-tabname. But I don't know how to build the WHERE condition for my SQL in this case.

In my original idea, I will get the key fields from table DD03L by the table name itab-tabname, and get the data element for the this table's key field, then I use the data elements to get the field length for each key data element from table DD04L. At last I can know each key fields and it lenth, then I want to use off-set of

itab-tabkey by knowing key field's length to combine my WHERE condition. At this point I don't know how to do it.

If my idea is right, can any experts give me a solution for this dynamic SQL??

If my idea is wrong, can any experts give me a right solutions??

Now I give an example for the ITAB.

P.S,

Client: 222

company code: 1000

Purchase Org: 1001

Sales Org: 1001

Vendor:1001000000

Customer:3001000000

tabname tabkey

LFA1 2221001000000

LFB1 22210010000001000

LFM1 22210010000001001

KNA1 2223001000000

KNB1 22230010000001000

KNVV 22230010000001001

former_member249594 · ‎09-19-2007

Hi Experts,

Any update on this topic. It is quite urgent. <b><REMOVED BY MODERATOR></b>

Message was edited by:

Alvaro Tejada Galindo

Former Member · ‎09-19-2007

Here is a program which was previously posted on this site for dynamic selection. I hope this helps you.

REPORT z_dynamic_selection LINE-SIZE 80

LINE-COUNT 64

MESSAGE-ID zz

NO STANDARD PAGE HEADING.

*----

*Tables *

*----

TABLES: sscrfields, "Fields on selection screens

dd03l. "Table Fields

*----

*Type Pools *

*----

TYPE-POOLS:rsds.

*----

*Selection Screen *

*----

SELECTION-SCREEN: BEGIN OF BLOCK b1 WITH FRAME TITLE text-001,

SKIP,

BEGIN OF LINE,

COMMENT 1(5) text-002.

PARAMETERS: p_tab LIKE dd03l-tabname OBLIGATORY. "Table name

SELECTION-SCREEN : PUSHBUTTON 45(8) p_btn USER-COMMAND clk, "Select-options

END OF LINE,

END OF BLOCK b1.

*----

*Types *

*----

TYPES: BEGIN OF t_dd03l,

tabname LIKE dd03l-tabname, "Table Name

fieldname LIKE dd03l-fieldname, "Field Name

keyflag LIKE dd03l-keyflag, "Key Flag

rollname LIKE dd03l-rollname, "Roll Name

position LIKE dd03l-position, "Position

ddtext(30), "Description

END OF t_dd03l.

TYPES: BEGIN OF t_fields.

INCLUDE STRUCTURE dd03l.

TYPES: END OF t_fields.

TYPES: BEGIN OF t_tabs. "To hold the table names

INCLUDE STRUCTURE rsdstabs.

TYPES: END OF t_tabs.

TYPES: BEGIN OF t_flds. "To hold the field names

INCLUDE STRUCTURE rsdsfields.

TYPES: END OF t_flds.

TYPES: BEGIN OF t_fname, "To hold the field names

fld LIKE dd03l-fieldname,

END OF t_fname.

*----

*Internal Tables *

*----

DATA: it_dd03l TYPE TABLE OF t_dd03l, "To hold the field names

it_tabs TYPE TABLE OF t_tabs, "To hold the table names

it_flds TYPE TABLE OF t_flds, "To hold the field names

it_temp TYPE TABLE OF t_flds, "Temp. table to hold field names

it_fields TYPE TABLE OF t_fields, "To hold the field names

it_cat TYPE TABLE OF lvc_s_fcat, "To hold Field Catalog

it_fname TYPE TABLE OF t_fname.

*----

*Work areas *

*----

DATA: d_ref TYPE REF TO data , "Data reference

wa_dd03l LIKE LINE OF it_dd03l, "Workarea for IT_DD03L

wa_tabs LIKE LINE OF it_tabs, "Workarea for IT_TABS

wa_flds LIKE LINE OF it_flds, "Workarea for IT_FLDS

wa_temp LIKE LINE OF it_temp, "Workarea for IT_TEMP

wa_fields LIKE LINE OF it_fields, "Workarea for IT_FIELDS

wa_cat LIKE LINE OF it_cat , "Workarea for IT_CAT

wa_fname LIKE LINE OF it_fname. "Workarea for IT_FNAME

*----

*Field Symbols *

*----

FIELD-SYMBOLS : <f_fs> TYPE table. "FieldSymbol for holding fields

*----

*Variables *

*----

DATA: gx_texpr TYPE rsds_texpr, "Variable to hold Expression

gx_twhere TYPE rsds_twhere, "Variable to hold Where Clause

gv_selid LIKE rsdynsel-selid, "Variable to hold Selid

gv_actnum LIKE sy-tfill, "Variable to hold no of fields

gv_title LIKE sy-title, "Variable to hold Title

gv_where_cl(100) TYPE c, "Variable to hold Where clause

gv_tbname LIKE dd03l-tabname,

gv_temp.

SELECT-OPTIONS: s_fld FOR dd03l-fieldname NO-DISPLAY, "To hold fields selected

s_selop FOR dd03l-fieldname NO-DISPLAY, "To hold fields for creating dyn. select-options

s_where FOR gv_where_cl NO-DISPLAY. "To hold where condition

PARAMETERS: gv_t_old LIKE dd03l-tabname NO-DISPLAY. "Earlier Table name

DATA: gt_grid TYPE REF TO cl_gui_alv_grid,

gt_cust TYPE REF TO cl_gui_custom_container, "Custom Container

cust TYPE scrfname VALUE 'CC_OUTPUT'. "Custom controller

*----

*Constants *

*----

CONSTANTS: gc_i TYPE c VALUE 'I',

gc_eq(2) TYPE c VALUE 'EQ'.

*----

*Initialization *

*----

INITIALIZATION.

**--Initialize values

PERFORM initialize.

*----

*At Selection Screen *

*----

AT SELECTION-SCREEN.

**--Select the fields of the input table

PERFORM select_flds.

*----

*Start Of Selection *

*----

START-OF-SELECTION.

**--Fetch data to display output

PERFORM fetch_data.

*----

*End Of Selection *

*----

END-OF-SELECTION.

CALL SCREEN '0300'.

*----

*At User Command *

*----

AT USER-COMMAND.

CASE sy-ucomm.

WHEN 'OK'.

REFRESH it_temp.

CLEAR it_temp.

MOVE 'S' TO wa_temp-type.

MOVE gv_tbname TO wa_temp-tablename.

DO.

READ LINE sy-index FIELD VALUE gv_temp INTO gv_temp.

IF sy-subrc NE 0.

EXIT.

ENDIF.

IF gv_temp EQ 'X'.

sy-index = sy-index - 1.

READ TABLE it_dd03l INTO wa_dd03l INDEX sy-index.

IF sy-subrc = 0.

MOVE wa_dd03l-fieldname TO wa_temp-fieldname.

APPEND wa_temp TO it_temp.

CLEAR gv_temp.

ENDIF.

ENDDO.

DESCRIBE TABLE it_temp.

IF sy-tfill GT 70.

**--More than 70 fields can not be selected

MESSAGE i001 WITH 'Cannot select more than 70 Parameters'(006).

REFRESH it_temp[]. CLEAR it_temp.

ELSE.

LEAVE LIST-PROCESSING.

ENDIF.

WHEN 'CANCEL'.

LEAVE LIST-PROCESSING.

WHEN 'SELALL'.

**--Select all fields

CLEAR wa_dd03l-fieldname.

DO.

READ LINE sy-index.

IF sy-subrc EQ 0 AND

wa_dd03l-fieldname NE space.

gv_temp = 'X'.

MODIFY LINE sy-index INDEX 0 FIELD VALUE gv_temp.

HIDE gv_temp.

CLEAR wa_dd03l-fieldname.

ELSEIF sy-subrc NE 0.

EXIT.

ENDIF.

ENDDO.

WHEN 'DSELALL'.

**--Deselect all fields

CLEAR gv_temp.

DO.

READ LINE sy-index.

IF sy-subrc EQ 0.

CLEAR gv_temp.

MODIFY LINE sy-index INDEX 0 FIELD VALUE gv_temp FROM gv_temp.

HIDE gv_temp.

ELSEIF sy-subrc NE 0.

EXIT.

ENDIF.

ENDDO.

ENDCASE.

sy-lsind = 0.

*&----

*& Form INITIALIZE

*&----

Initialize values on selection-screen

*----

FORM initialize .

p_btn = 'Options'(003).

ENDFORM. " INITIALIZE

*&----

*& Form SELECT_FLDS

*&----

Select fields from the table

*----

FORM select_flds .

CASE sscrfields-ucomm.

WHEN 'CLK'.

**--Display Screen with the list of fields

PERFORM genr_scr.

ENDCASE.

ENDFORM. " SELECT_FLDS

*&----

*& Form genr_scr

*&----

Display a screen with list of fields

*----

FORM genr_scr.

**--If table in the parameter is not the same as the old table and

**--old table is not blank, then initialise all the variables associated

IF p_tab NE gv_t_old AND gv_t_old IS NOT INITIAL.

REFRESH: it_tabs, it_flds,

gx_texpr, gx_twhere,

s_where, s_selop.

CLEAR: gv_selid.

**--Pass current table parameter value to Old table parameter

gv_t_old = p_tab.

ENDIF.

**--Pass the current table name to old table variable

IF gv_t_old EQ space.

gv_t_old = p_tab.

ENDIF.

**--Check if table name is given before clicking the button

IF p_tab IS INITIAL.

MESSAGE e001 WITH 'Enter the Table name'(004).

ENDIF.

**--Get the list of fields of a given table

PERFORM get_selections.

**--If none of the fields, provide the list of fields for selecting

IF it_flds[] IS INITIAL.

CLEAR gv_selid.

PERFORM select_fieldlist.

ENDIF.

**--Show message if none of the fields are selected

IF it_flds[] IS INITIAL.

MESSAGE s001 WITH 'No parameters selected'(005).

EXIT.

ENDIF.

**--Generate dynamic select-options

REFRESH it_tabs.

CLEAR : it_tabs, wa_tabs.

wa_tabs-prim_tab = p_tab.

APPEND wa_tabs TO it_tabs.

PERFORM set_values.

**--Generate Expression from Where clause

CALL FUNCTION 'FREE_SELECTIONS_WHERE_2_EX'

EXPORTING

where_clauses = gx_twhere

IMPORTING

expressions = gx_texpr

EXCEPTIONS

incorrect_expression = 1

OTHERS = 2.

IF sy-subrc NE 0.

MESSAGE i001 WITH 'Error in Dynamic screen generation'(009).

EXIT.

ENDIF.

IF gx_texpr IS NOT INITIAL.

**--Populate values to select-options from expression

PERFORM set_values.

ENDIF.

**--Display screen with the fields listed

IF gv_selid IS NOT INITIAL.

PERFORM call_screen.

ENDIF.

ENDFORM. " genr_scr

*&----

*& Form GET_SELECTIONS

*&----

Fetch the fields in the table given

*----

FORM get_selections.

DATA : wa_where LIKE LINE OF gx_twhere.

REFRESH: it_flds, gx_twhere.

CLEAR : wa_flds.

wa_flds-tablename = p_tab.

wa_flds-type = 'S'.

LOOP AT s_selop.

**--Populate all the fields selected that are previously selected

wa_flds-fieldname = s_selop-low.

APPEND wa_flds TO it_flds.

ENDLOOP.

IF s_where[] IS NOT INITIAL.

**--Populate values to where condition if any data is previously given

**--to the dynamic select-options

wa_where-tablename = p_tab.

LOOP AT s_where.

APPEND s_where-low TO wa_where-where_tab.

ENDLOOP.

APPEND wa_where TO gx_twhere.

ENDIF.

ENDFORM. " GET_SELECTIONS

*&----

*& Form SELECT_FIELDLIST

*&----

Display the list of fields

*----

FORM select_fieldlist.

CLEAR: it_dd03l[], it_dd03l,

gv_tbname.

**--Get field names for given table

SELECT tabname

fieldname

keyflag

rollname

position

FROM dd03l

INTO TABLE it_dd03l

WHERE tabname EQ p_tab

AND fieldname NE 'MANDT'.

IF sy-subrc = 0.

SORT it_dd03l BY position.

DELETE it_dd03l WHERE fieldname CP '.INCLU*'.

ENDIF.

**--Get the description of the fields

LOOP AT it_dd03l INTO wa_dd03l.

IF NOT wa_dd03l-rollname IS INITIAL.

SELECT SINGLE ddtext

FROM dd04t

INTO wa_dd03l-ddtext

WHERE rollname EQ wa_dd03l-rollname

AND ddlanguage = sy-langu

AND as4local = 'A'.

MODIFY it_dd03l FROM wa_dd03l.

ELSE.

SELECT SINGLE ddtext

FROM dd03t

INTO wa_dd03l-ddtext

WHERE tabname EQ wa_dd03l-tabname

AND ddlanguage = sy-langu

AND as4local = 'A'

AND fieldname = wa_dd03l-fieldname.

MODIFY it_dd03l FROM wa_dd03l.

ENDIF.

ENDLOOP.

gv_tbname = p_tab.

**--Display screen with the fields listed for the given table

CALL SCREEN 200 STARTING AT 10 2

ENDING AT 70 22.

**--Clear all the fields selected

CLEAR : it_flds, it_flds[], gv_tbname.

**--Populate the newly selected fields

it_flds[] = it_temp[].

**--Clear temporary table with the fields selected

CLEAR : it_temp, it_temp[].

ENDFORM. " SELECT_FIELDLIST

*&----

*& Form INITIALIZE_SCREEN

*&----

text

*----

FORM initialize_screen.

CALL FUNCTION 'FREE_SELECTIONS_INIT'

EXPORTING

kind = 'T'

expressions = gx_texpr

IMPORTING

selection_id = gv_selid

number_of_active_fields = gv_actnum

TABLES

tables_tab = it_tabs

fields_tab = it_flds

EXCEPTIONS

fields_incomplete = 01

fields_no_join = 02

field_not_found = 03

no_tables = 04

table_not_found = 05

expression_not_supported = 06

incorrect_expression = 07

illegal_kind = 08

area_not_found = 09

inconsistent_area = 10

kind_f_no_fields_left = 11

kind_f_no_fields = 12

too_many_fields = 13.

ENDFORM. " INITIALIZE_SCREEN

*&----

*& Form SET_VALUES

*&----

Set the values to the select-options

*----

FORM set_values.

CALL FUNCTION 'FREE_SELECTIONS_INIT'

EXPORTING

kind = 'T'

expressions = gx_texpr

IMPORTING

selection_id = gv_selid

number_of_active_fields = gv_actnum

TABLES

tables_tab = it_tabs

fields_tab = it_flds

EXCEPTIONS

fields_incomplete = 01

fields_no_join = 02

field_not_found = 03

no_tables = 04

table_not_found = 05

expression_not_supported = 06

incorrect_expression = 07

illegal_kind = 08

area_not_found = 09

inconsistent_area = 10

kind_f_no_fields_left = 11

kind_f_no_fields = 12

too_many_fields = 13.

ENDFORM. " SET_VALUES

*&----

*& Form CALL_SCREEN

*&----

Call the screen to display the fields

*----

FORM call_screen.

DATA : wa_where LIKE LINE OF gx_twhere,

lv_txt TYPE string.

lv_txt = 'Dynamic Selections Parameters for'(007).

CONCATENATE lv_txt p_tab

INTO gv_title SEPARATED BY space.

CALL FUNCTION 'FREE_SELECTIONS_DIALOG'

EXPORTING

selection_id = gv_selid

title = gv_title

tree_visible = ' '

IMPORTING

where_clauses = gx_twhere

expressions = gx_texpr

number_of_active_fields = gv_actnum

TABLES

fields_tab = it_flds

EXCEPTIONS

internal_error = 01

no_action = 02

no_fields_selected = 03

no_tables_selected = 04

selid_not_found = 05.

IF sy-subrc EQ 0.

REFRESH: s_where, s_selop.

**--Populate the Where clause with selected values

s_where-sign = gc_i.

s_where-option = gc_eq.

CLEAR wa_where.

READ TABLE gx_twhere INDEX 1 INTO wa_where.

LOOP AT wa_where-where_tab INTO s_where-low.

APPEND s_where.

ENDLOOP.

**--Populate all the fields

s_selop-sign = gc_i.

s_selop-option = gc_eq.

CLEAR : wa_flds.

LOOP AT it_flds INTO wa_flds.

s_selop-low = wa_flds-fieldname.

APPEND s_selop.

ENDLOOP.

ENDIF.

ENDFORM. " CALL_SCREEN

*&----

*& Module STATUS_0200 OUTPUT

*&----

Display screen with select-options

*----

MODULE status_0200 OUTPUT.

DATA: lv_txt TYPE string.

lv_txt = 'Selection Paramters List'(008).

SET PF-STATUS 'DIALOG'.

LEAVE TO LIST-PROCESSING AND RETURN TO SCREEN 0.

SUPPRESS DIALOG.

MOVE lv_txt TO sy-title.

**--display list of fields that can be selected for creating dynamic select-options

LOOP AT it_dd03l INTO wa_dd03l.

AT FIRST.

WRITE: (60) sy-uline.

ENDAT.

READ TABLE it_flds INTO wa_flds WITH KEY fieldname = wa_dd03l-fieldname.

IF sy-subrc NE 0.

CLEAR gv_temp.

ELSE.

gv_temp = 'X'.

ENDIF.

WRITE:/ '|' ,gv_temp AS CHECKBOX.

WRITE: (20) wa_dd03l-fieldname,'|', wa_dd03l-ddtext, AT 60 '|'.

HIDE: gv_temp, wa_dd03l-fieldname, wa_dd03l-keyflag.

AT LAST.

WRITE: (60) sy-uline.

ENDAT.

ENDLOOP.

ENDMODULE. " STATUS_0200 OUTPUT

*&----

*& Form FETCH_DATA

*&----

Fetch data from table

*----

FORM fetch_data .

DATA: lv_where TYPE string,

lv_cnt TYPE i.

**--Check for the existance of the table

SELECT *

FROM dd03l

INTO TABLE it_fields

WHERE tabname = p_tab.

SORT it_fields BY position.

**--Delete the fields starting with .INCLU

DELETE it_fields WHERE fieldname CP '.INCLU*'.

**--Display the first 150 fields of the table

LOOP AT it_fields INTO wa_fields TO 150.

lv_cnt = lv_cnt + 1.

wa_cat-tabname = p_tab.

wa_cat-fieldname = wa_fields-fieldname.

wa_cat-col_pos = lv_cnt.

wa_cat-inttype = wa_fields-inttype.

wa_cat-datatype = wa_fields-datatype.

wa_cat-intlen = wa_fields-intlen.

wa_cat-seltext = wa_fields-fieldname.

wa_cat-decimals = wa_fields-decimals.

wa_cat-ref_field = wa_fields-fieldname.

wa_cat-ref_table = p_tab.

APPEND wa_cat TO it_cat.

CLEAR wa_cat.

wa_fname-fld = wa_fields-fieldname.

APPEND wa_fname TO it_fname.

CLEAR wa_fname.

ENDLOOP.

**--Create a dynamic internal table with the 150 fields

CALL METHOD cl_alv_table_create=>create_dynamic_table

EXPORTING

it_fieldcatalog = it_cat

IMPORTING

ep_table = d_ref.

ASSIGN d_ref->* TO <f_fs>.

**--Populate the Where clause as a string

LOOP AT s_where.

CONCATENATE lv_where s_where-low INTO lv_where SEPARATED BY space.

ENDLOOP.

**--Select the data from the table given as input and populate

**--it into the dynamic internal table created based on the where condition

SELECT (it_fname)

FROM (p_tab)

INTO CORRESPONDING FIELDS OF TABLE <f_fs>

WHERE (lv_where).

**--If no entries are found that satisfies the selection criteria

IF sy-subrc <> 0.

MESSAGE i000(zz) WITH 'No data found'(010).

ENDIF.

ENDFORM. " FETCH_DATA

*&----

*& Form DISPLAY_DATA

*&----

Display data in the grid control

*----

FORM display_data .

IF gt_cust IS INITIAL.

CREATE OBJECT gt_cust

EXPORTING

container_name = cust .

CREATE OBJECT gt_grid

EXPORTING

i_parent = gt_cust.

**--Display the data in the grid control

CALL METHOD gt_grid->set_table_for_first_display

EXPORTING

i_buffer_active = 'X'

i_bypassing_buffer = ' '

I_CONSISTENCY_CHECK =
I_STRUCTURE_NAME =
IS_VARIANT =
I_SAVE =
I_DEFAULT = 'X'
IS_LAYOUT =
IS_PRINT =
IT_SPECIAL_GROUPS =
IT_TOOLBAR_EXCLUDING =
IT_HYPERLINK =
IT_ALV_GRAPHICS =
IT_EXCEPT_QINFO =
IR_SALV_ADAPTER =

CHANGING

it_outtab = <f_fs>

it_fieldcatalog = it_cat

IT_SORT =
IT_FILTER =

EXCEPTIONS

invalid_parameter_combination = 1

program_error = 2

too_many_lines = 3

OTHERS = 4

.

IF sy-subrc <> 0.

ENDIF.

ENDFORM. " DISPLAY_DATA

*&----

*& Module DISPLAY_DATA OUTPUT

*&----

Dispaly data in the output

*----

MODULE display_data OUTPUT.

PERFORM display_data.

ENDMODULE. " DISPLAY_DATA OUTPUT

*&----

*& Module STATUS_0300 OUTPUT

*&----

Pf-status for the screen

*----

MODULE status_0300 OUTPUT.

SET PF-STATUS '13317'.

ENDMODULE. " STATUS_0300 OUTPUT

*&----

*& Module USER_COMMAND_0300 INPUT

*&----

Handling the button clicks

*----

MODULE user_command_0300 INPUT.

CASE sy-ucomm.

**--Go to the previous screen

WHEN 'BACK'.

LEAVE TO SCREEN 0.

**--Come out of the program

WHEN 'EXIT'.

LEAVE PROGRAM.

ENDCASE.

ENDMODULE. " USER_COMMAND_0300 INPUT

former_member249594 · ‎09-20-2007

Hi Fred Morsell

Thanks for your kindly response. I had copied your source code to my SAP and tried to run it. But there have some screen is missed,for example screen 200. And then I created the screen for my program, but I do nkot know which field should be in the screen and what is its attributes. Would you please provide the screen information which related to this program also? thanks.

Former Member · ‎09-20-2007

Hi Joe,

Just create the screens 200 and 300 as empty screens. As they are nothing but containers. The program dynamically builds and displays the data on the screens.

former_member249594 · ‎09-21-2007

Hi Fred,

Thanks you. But I had got my solution before you replied.

Actually the coding provided by you is more flexible and more functionality, and can meet a complex selection options. I will study your solution after completing my task. And update you the coding of my solution:

l_table_name = tt_change_field-tabname.

SELECT dd03l~tabname

dd03l~fieldname

dd03l~position

dd03l~rollname

dd04l~leng

INTO CORRESPONDING FIELDS OF TABLE lt_key_field

FROM dd03l INNER JOIN dd04l

ON dd03l_{rollname = dd04l}rollname

WHERE dd03l~tabname = l_table_name

AND dd03l~as4local = 'A'

AND dd03l~keyflag = 'X'.

IF lt_key_field[] IS INITIAL.

MESSAGE 'Error occurs when getting tabke key fields' TYPE 'E'.

ELSE.

l_off_set = 0.

SORT lt_key_field BY position.

LOOP AT lt_key_field.

IF sy-tabix NE 1.

CONCATENATE l_where 'AND' INTO l_where SEPARATED BY space.

ENDIF.

CONCATENATE l_where

lt_key_field-fieldname

'EQ'

l_single_quotes

INTO l_where

SEPARATED BY space.

CONCATENATE l_where

lt_editpos-tabkey+l_off_set(lt_key_field-leng)

l_single_quotes

INTO l_where.

l_key_length = l_off_set + lt_key_field-leng.

IF l_key_length >= lt_editpos-keylen.

EXIT.

ENDIF.

l_off_set = lt_key_field-leng + l_off_set.

ENDLOOP.

FREE l_ref_struc.

CLEAR: <ls_struc>,<l_field>.

CREATE DATA l_ref_struc TYPE (l_table_name).

ASSIGN l_ref_struc->* TO <ls_struc>.

l_subrc = sy-subrc.

IF l_subrc NE 0.

RAISE ex_assign_table_struc_error.

EXIT.

ENDIF.

SELECT SINGLE * FROM (l_table_name)

INTO CORRESPONDING FIELDS OF <ls_struc>

WHERE (l_where).

l_subrc = sy-subrc.

IF l_subrc NE 0.

RAISE ex_can_not_get_the_table_value.

EXIT.

ENDIF.

ASSIGN COMPONENT tt_change_field-fieldname

OF STRUCTURE <ls_struc>

TO <l_field>.

tt_change_field-value = <l_field>.

MODIFY tt_change_field.

ENDIF."key field is not initial

How to select a single value from a table dynamically by its table key