topic Re: String pattern matching in where clause in Application Development and Automation Discussions

String pattern matching in where clause

matteo_montalto — Fri, 18 May 2012 08:04:06 GMT

Hi all gurus,

my requirement: I'm working on an internal table and I have to loop on elements whose field MATNR meets a specific pattern.

MATNR is a string (CHAR40) and could contain both numeric digits and characters.

Supposing I get a NUMERIC field, say '1234', I have to loop on the itab just for the element which meets the following pattern:

X1234

where X could be a sequence of zeroes (even a null sequence). So, just to remain on the example,

MATNR = 1234

match the pattern, as well as MATNR = 0001234 and MATNR = 01234.

To provide another example, MATNR = 000A0001234 does NOT match the pattern, as well as MATNR = 1243 or MATNR = 000100001234.

I'm wondering if there's a way to render this pattern via operators in ABAP. As far as I've seen, the CP operator does not allow to render "an arbitrally long set of zeroes" expression.

Closest I can imagine is:

LOOP AT internal_table INTO workarea
WHERE matnr CP pattern
AND matnr NA SY-ABCDE.

where pattern = '*1234'. Such a clause is almost correct, as doesn't exclude cases like '00001000001234' as I can't find a way to tell the prefix should be a sequence of zeroes.

Any idea is welcome.

Re: String pattern matching in where clause

Former Member — Fri, 18 May 2012 08:14:30 GMT

Why dont you use MATNR as TYPE N (40) and have the same in the internal table?

So when you assign 1234 it will prefix 36 zeroes to the variable.

Thoughts?

Re: String pattern matching in where clause

matteo_montalto — Fri, 18 May 2012 08:42:08 GMT

Hi Shambu,

unfortunately, I cannot change data declaration.

Actually, there's a workaround for the specific issue:

supposing: pattern = '*1234';

key = '1234'.

I could do as follows:

LOOP AT internal_table INTO workarea
WHERE matnr CP pattern
AND matnr NA SY-ABCDE.

    CALL FUNCTION 'CONVERSION_EXIT_ALPHA_OUTPUT'
           EXPORTING
             input = workarea-matnr
           IMPORTING
             output = tmp_prod_id.

IF tmp_prod_id <> key.

EXIT.

ELSE.

"code

....

Just for curiosity, I was looking if there's a way to render the condition on a specific WHERE statement clause.

Re: String pattern matching in where clause

ThomasZloch — Fri, 18 May 2012 08:47:53 GMT

I don't think there is one right at the WHERE-condition. In addition to your approach above, you could try finding a regular expression that serves your purpose and use it in a FIND statement inside the loop.

Thomas

Re: String pattern matching in where clause

Former Member — Fri, 18 May 2012 09:21:43 GMT

Hi,

Just try this simple program. I used conversion exit to remove leading zeros. Hope it helps.

DATA: itab TYPE TABLE OF makt,
       wa LIKE LINE OF itab.
 
 DATA: g_matnr TYPE matnr VALUE '1234'.
 
 wa-matnr = '000100001234'.
 APPEND wa TO itab.
 
 wa-matnr = '00A1234'.
 APPEND wa TO itab.
 
 wa-matnr = '0001234'.
 APPEND wa TO itab.
 
 wa-matnr = '01234'.
 APPEND wa TO itab.
 
 wa-matnr = '1243'.
 APPEND wa TO itab.
 
 
 CLEAR: wa.
 LOOP AT itab INTO wa WHERE matnr NA sy-abcde.
 
   WRITE:/ wa-matnr.
 
   CALL FUNCTION 'CONVERSION_EXIT_ALPHA_OUTPUT'
     EXPORTING
       input  = wa-matnr
     IMPORTING
       output = wa-matnr.
 
   WRITE: wa-matnr.
 
   IF wa-matnr EQ g_matnr.
     WRITE: 'YES'.
   ELSE.
     WRITE: 'NO'.
   ENDIF.
 
 ENDLOOP.

Sample Output:

Regards,
Jake

Re: String pattern matching in where clause

kesavadas_thekkillath — Fri, 18 May 2012 09:23:07 GMT

if you have say lv_field1 = X1234.

Just consider the length as 4 removing the X. Now while looping just use the statement like

len1 = 4 "length of X1234

write lv_field into lv_field using edit mask '==ALPHA'.

len = strlen( lv_field ).

if len = len1. "if both lenght are same

then true

if lv_field1 = lv_field. "if both values re same

then true.

else.

false.

else

false

endif.

Hope it helps.

Re: String pattern matching in where clause

matteo_montalto — Fri, 18 May 2012 09:42:09 GMT

Jake, that's the workaround I used and described in my post above... Thanks anyway!

Kesavadas; unfortunately there's no fixed-number-of-digits for MATNR... I should then count the length of any key I have to process.

Anyway, thank you all, I desume there's no way to express such a pattern matching rule in the WHERE clause of the main loop. As far as my workaround works, I can close the discussion