Why is there a data type NUMC?

[lbreddemann]

Hi ABAP masters,

working in database support for several years I've very often seen the problems that arise from the awkward data type NUMC.

A numeric type stored as characters.

What I always wondered is: what is this data type really good for?

The leading zero output display alone is hardly a valid reason to waste storage and complicate the usage of the data of that type.

I cannot imagine any use for this data type that wouldn't be better done by using integer types.

So, if you know what the reasoning behind this data type is, please let me know.

thanks and best regards,

Lars

[former_member194669]

One advantage for NUMC will be maximum length

NUMC = 1-255

I think for Integer

INT1 = 3

INT2 = 5

INT4 = 10

a®

[lbreddemann]

Hello a®s,

that sounds reasonable, although I get the feeling that this is your best guess, is it?

But can you do anything with such large numbers (arithmetic operations?) or can you just store and retrieve them?

thanks and best regards,

Lars

[Former Member]

From what I understand, SAP can't buffer the tables unless the keys are in character type. The use of a numeric type with leading zeros stored as character is then necessary.

Altough I think I haven't seen an standard table key declared as numc, when that is necessary the alpha conversion is used against a character field

[lbreddemann]

> Altough I think I haven't seen an standard table key declared as numc, when that is necessary the alpha conversion is used against a character field

Hi Ramiro,

ahem... MANDT is NUMC, BUKRS is NUMC ...

regards,

Lars

---> I've to take that back a bit... MANDT is indeed CLNT (the 3 character version of NUMC...)

Edited by: Lars Breddemann on Aug 5, 2009 12:02 AM

[MarcinPciak]

Hi Lars,

Although it is indeed complicated in handling that data objects, there are some places where using them is better choice that using char types. I.e

- postal codes

- PO box numbers

- screen fields where only digits are allowed

Ok, you may say that above are examples of leading zeros usage but it's much easier to handle them as strings as well. When concatenating we don't have to worry about zeros we might forget in front of data objects, which of course can change value we are interested in - if not provided.

Very often happend to me that in excel when comparing some values (after importing some data file) I forgot about leading zeros (i.e for some SUBTYPE field) which turned out be a pay in the neck before I indentified the issue. That's why I really appreciate N type in ABAP

Also range should be of special importance here. Max bytes for N is 65535, while for integer is only 4 bytes, which implies what a®s said about field length.

Regards

Marcin

[Former Member]

when number ,character and arithmetic operation are required  

[Former Member]

• NUMC data type can be used to maintain positive numbers with leading Zeros
• Most of SAP's important numbers like Sales Order numbers, Customer numbers, Delivery documents,
• Material numbers, Sales Org, Division, Company Codes, Distribution Channel are CHARs only
• But if their Data is containing only digits, SAP Transactions will automatically add Leading zeros for them and store in the database as Raw data.
• If those SAP numbers contains at least one non-digit character, then leading zeros will not be added.
• Example: if 54 is assigned to BUKRS it will be stored in DB as 0054

               if 5A is assigned to BUKRS it will be stored in DB as 5A only

• Leading zero concept is very useful for Date and Time calculations.
• Month, Day, hours etc., must be declared as NUMC for better calculations

Example:

    PARAMETERS p_year TYPE I.          "instead of Integer we can use type N LENGTH 4 also here

    DATA  v_month TYPE N LENGTH 2.

    DATA  v_day     TYPE N LENGTH 2.

    DATA  v_year    TYPE N LENGTH 4.       then calculations will be easy

    DATA  FDATE   TYPE D.

    v_year = p_year.

    v_day  = 1.              "1st day of Month

    DO 12 TIMES.

        v_month = sy-index.           "Leading zero will be added automatically

        CONCATENATE v_year  v_month  v_day  INTO  FDATE.

        WRITE / FDATE.                "Every month 1st day of selected year

    ENDDO. 

Example:  Customer number contains uneven digits.  It should be converted to a 10 digit number

                 with "C" as 1st Character.  Logic will be

                 PARAMETERS custno TYPE I.               

                 DATA  v1                     TYPE  N  LENGTH  10.

                 DATA  str_custno         TYPE C LENGTH 11.

                 v1 = custno.       "customer number will be converted to 10 digit number

                 CONCATENATE 'C'  V1   INTO  str_custno.

please correct me, if I am wrong

Thanks and Regards

Nagababu Tubati

[rosenberg_eitan]

Hi,

Numc fields can be concatenated.

Have a look at http://scn.sap.com/docs/DOC-47512 and the program included :

*----------------------------------------------------------------------*

TYPES: BEGIN OF tp_vald_1 .

* Note the RENAMING WITH SUFFIX .

        INCLUDE TYPE tp_ent_xxx AS ent_001 RENAMING WITH SUFFIX _ent_001 .

        INCLUDE TYPE tp_ent_xxx AS ent_002 RENAMING WITH SUFFIX _ent_002 .

        INCLUDE TYPE tp_ent_xxx AS ent_003 RENAMING WITH SUFFIX _ent_003 .

        INCLUDE TYPE tp_ent_xxx AS ent_004 RENAMING WITH SUFFIX _ent_004 .

        INCLUDE TYPE tp_ent_xxx AS ent_005 RENAMING WITH SUFFIX _ent_005 .

        INCLUDE TYPE tp_ent_xxx AS ent_006 RENAMING WITH SUFFIX _ent_006 .

        INCLUDE TYPE tp_ent_xxx AS ent_007 RENAMING WITH SUFFIX _ent_007 .

        INCLUDE TYPE tp_ent_xxx AS ent_008 RENAMING WITH SUFFIX _ent_008 .

        INCLUDE TYPE tp_ent_xxx AS ent_009 RENAMING WITH SUFFIX _ent_009 .

        INCLUDE TYPE tp_ent_xxx AS ent_010 RENAMING WITH SUFFIX _ent_010 .

        INCLUDE TYPE tp_ent_xxx AS ent_011 RENAMING WITH SUFFIX _ent_011 .

        INCLUDE TYPE tp_ent_xxx AS ent_012 RENAMING WITH SUFFIX _ent_012 .

        INCLUDE TYPE tp_ent_xxx AS ent_013 RENAMING WITH SUFFIX _ent_013 .

           col_pos     TYPE n LENGTH 3 ,

        CONCATENATE 'ENT_' <st_alv_hdrc_1>-col_pos INTO fieldname .

    * Get specific week entry

        ASSIGN COMPONENT fieldname OF STRUCTURE st_bffr_8 TO <st_ent_xxx> .

    <st_ent_xxx>-paymentsum      = <st_sflight>-paymentsum .

Regards .

[lbreddemann]

Dear all

I am quite surprised to see this ancient thread coming to life again

In order to close the thread I assigned "correct answer" now to the first 'grave digger' from 2012 and "helpful answer" to every other contributor. Please note that this is not meant as a valuation of your contribution, I really appreciate every one of them.

My conclusion is: NUMC is handy for list processing of formatted numbers - just that .

As it is in principle possible to convert NUMC to a numeric data type and vice versa, there is not a hard functional limitation present with numeric data types.

NUMC simply is more easy to use for certain use cases.

Thanks again everybody,

Lars

[glenleslie]

hehe... and once again in DWC + BW Bridge...