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ABAP DESCRIBE FIELD INTO Statement syntax, information and example SAP source code
DESCRIBE FIELD INTO
ABAP Syntax DESCRIBE FIELD dobj INTO td.
What does it do? All characteristics of the f field, its components, subcomponents, and so on, are displayed in the td field ( type description ). td must be of type SYDES_DESC
, which is defined in type group SYDES .
The SYDES_DESC structure has two table-like components,
TYPES and NAMES :
In TYPES , the tree structure of the type belonging to f is mapped. The components of a node are stored close together in table TYPES . The beginning and end of the line area that represents the components are stored in TYPES-FROM and
TYPES-TO . The reference to the higher-level node can be found in
TYPES-BACK . If there is no higher-level or subordinate node, this is indicated by the value 0 (for the meaning of further components, see the following sections).
The names of components, types, and so on are not stored in
TYPES directly. Instead, the components TYPES-IDX_... each have an index in name table NAMES . The value 0 indicates that there is no reference to the name table.
In component NAMES-NAME , NAMES contains the (possibly fragmented) names. If a name continues in the following line, this is indicated by an asterisk ('*') in the component NAMES-CONTINUE .
The type description table ( TYPES ) not only stores information about the tree structure but also further information about the type of f and its components. This particularly includes all information that can be determined using the usual additions to
. TYPES contains the following columns:
IDX_NAME Component name
IDX_USER_TYPE Name of a user-defined type, that is, a type that was defined by a TYPES statement. Derived types (<(>... TYPE A-B<)>) and structures from the ABAP Dictionary are not considered to be user-defined types.
CONTEXT For user-defined types only: The context in which the type is defined. Possible values are defined in the
SYDES_CONTEXT constants of type group
SYDES . Use these constants for comparison purposes only. A distinction is made between the following type contexts:
SYDES_CONTEXT-PROGRAM : Program-global type
SYDES_CONTEXT-FORM : Local FORM type
SYDES_CONTEXT-FUNCTION : Local FUNCTION type
SYDES_CONTEXT-METHOD : Local METHOD type
IDX_CONTEXT_NAME For user-defined types only:
With a local context: The name of the FORM or FUNCTION in which the type was defined. The name of the associated program is then the first entry in the name table.
With a global context: The name of the program in which the type was defined.
IDX_EDIT_MASK Conversion routine from the ABAP Dictionary, corresponds to the EDIT MASK addition with a simple DESCRIBE
IDX_HELP_ID Help ID when referencing fields from the ABAP Dictionary
LENGTH Internal length, corresponds to the LENGTH
addition with a simple DESCRIBE
OUTPUT_LENGTH Output length, corresponds to the
OUTPUT-LENGTH addition with a simple DESCRIBE
DECIMALS Number of decimal digits
, corresponds to the DECIMALS addition with a simple
DESCRIBE
TYPE ABAP type, corresponds to the TYPE addition with a simple DESCRIBE . If DESCRIBE INTO is applied to a nested structure that contains a boxed component , the type is returned with the internal ID j (
static box ).
TABLE_KIND A table type is stored here for the components that represent an internal table. The same values are returned as for the variant DESCRIBE TABLE itab KIND k . Components that do not represent a table receive the return value SYDES_KIND-UNDEFINED (see type group SYDES ).
Example ABAP Coding Definition of the complex data type <(>EMPLOYEE_STRUC
<)>:
PROGRAM DESCTEST.
TYPES: BEGIN OF name_struc,
first TYPE c LENGTH 20,
last TYPE c LENGTH 20,
END OF name_struc,
BEGIN OF absence_time_struc,
day TYPE d,
from TYPE t,
to TYPE t,
END OF absence_time_struc,
phone_number TYPE n LENGTH 20,
BEGIN OF employee_struc,
id LIKE sbook-customid,
name TYPE name_struc,
BEGIN OF address,
street TYPE c LENGTH 30,
zipcode TYPE n LENGTH 4,
place TYPE c LENGTH 30,
END OF address,
salary_per_month TYPE p LENGTH 10 DECIMALS 3,
absent TYPE STANDARD TABLE OF absence_time_struc
WITH NON-UNIQUE DEFAULT KEY,
phone TYPE STANDARD TABLE OF phone_number
WITH NON-UNIQUE DEFAULT KEY,
END OF employee_struc.
You can determine the structure of the type by using type group SYDES as follows:
td TYPE sydes_desc.
DESCRIBE FIELD employee INTO td.
The following table shows a few selected columns of type description table TD-TYPES . For a better overview, the names of the columns IDX_NAME , IDX_UERR_TYPE , and IDX_EDIT_MASK
have been shortened:
---|----|----|----|----|----|----|----
01 | 2 | 7 | 0 | 0 | 2 | 0 | v
02 | 0 | 0 | 1 | 6 | 0 | 4 | N
03 | 8 | 9 | 1 | 7 | 5 | 0 | u
04 | 10 | 12 | 1 | 8 | 0 | 0 | u
05 | 0 | 0 | 1 | 9 | 0 | 0 | P
06 | 13 | 13 | 1 | 11 | 0 | 0 | h
07 | 17 | 17 | 1 | 12 | 0 | 0 | h
08 | 0 | 0 | 3 | 13 | 0 | 0 | C
09 | 0 | 0 | 3 | 14 | 0 | 0 | C
10 | 0 | 0 | 4 | 15 | 0 | 0 | C
11 | 0 | 0 | 4 | 16 | 0 | 0 | N
12 | 0 | 0 | 4 | 17 | 0 | 0 | C
13 | 14 | 16 | 6 | 0 | 18 | 0 | u
14 | 0 | 0 | 13 | 20 | 0 | 0 | D
15 | 0 | 0 | 13 | 21 | 0 | 0 | T
16 | 0 | 0 | 13 | 22 | 0 | 0 | T
17 | 0 | 0 | 7 | 0 | 0 | 0 | N
Note that the entries in rows 6 and 7 represent internal tables (
ABAP type h). There is always an entry for the corresponding row type (rows 13 and 17) for an internal table.
The indices in rows 5 to 7 refer to entries in name table
TD-NAMES . If you look, for example, at row 3, you find the corresponding component name in TD-NAMES from row 7 ( NAME ) onwards and the corresponding user type from row 5 ( NAME_STRUC ) onwards.
In name table TD-NAMES , you find the following entries. Note that the names <(>SALARY_PER_MONTH<)> and <(>ABSENCE_TIME_STRUC<)> are stored in two parts:
|CONTINUE|NAME |CONTINUE|NAME
---|--------|-------------- ----|--------|--------------
01 | |DESCTEST 12 | |PHONE
02 | |EMPLOYEE_STRUC 13 | |FIRST
03 | |SBOOK-CUSTOMID 14 | |LAST
04 | |==ALPHA 15 | |STREET
05 | |NAME_STRUC 16 | |ZIPCODE
06 | |ID 17 | |PLACE
07 | |NAME 18 | * |ABSENCE_TIME_ST
08 | |ADDRESS 19 | |RUC
09 | * |SALARY_PER_MONT 20 | |DAY
10 | |H 21 | |FROM
11 | |ABSENT 22 | |TO
Documentation extract taken from SAP system, � Copyright SAP AG. All rights reserved
