ABAP Keyword Documentation → ABAP - Reference → Processing External Data → Data Clusters → EXPORT
EXPORT - medium
Other versions: 7.31 | 7.40 | 7.54
Syntax
... { DATA BUFFER xstr }
| { INTERNAL TABLE itab }
| { MEMORY ID id }
| { DATABASE dbtab(ar) [FROM wa] [CLIENT cl] ID id }
| { SHARED MEMORY dbtab(ar) [FROM wa] [CLIENT cl] ID id }
| { SHARED BUFFER dbtab(ar) [FROM wa] [CLIENT cl] ID id } ...
Alternatives
1. ... DATA BUFFER xstr
2. ... INTERNAL TABLE itab
3. ... MEMORY ID id
4. ... DATABASE dbtab(ar) [FROM wa] [CLIENT cl] ID id
5. ... SHARED MEMORY dbtab(ar) [FROM wa] [CLIENT cl] ID id
6. ... SHARED BUFFER dbtab(ar) [FROM wa] [CLIENT cl] ID id
Effect
The exported data cluster can be stored in a byte string xstr
, in an internal table itab
, in the
ABAP memory, in a database table dbtab
, or in a shared memory area
(SHARED MEMORY
or BUFFER
specified) .
Alternative 1
... DATA BUFFER xstr
Effect
If DATA BUFFER
is specified, the data cluster is written to the elementary
data object xstr
, which has to be of the type xstring
. The previous content of xstr
is overwritten completely.
Notes
-
A data object
xstr
filled byEXPORT TO DATA BUFFER
contains exactly one data cluster. -
A common application of the addition
DATA BUFFER
is to store the generated data cluster in a field of a database table with the corresponding data type. In this case, consider compressing the data cluster using the addition COMPRESSION, since, by default, compression as a medium is only activated ifDATABASE
is specified directly. -
The content of a data object filled by
EXPORT TO DATA BUFFER
can only be evaluated usingIMPORT FROM DATA BUFFER
. In other evaluations, for example when comparing data clusters, the result is not defined. For example, the undefined content of alignment gaps in structures can result in different data clusters with structures that otherwise have the same content.
Alternative 2
... INTERNAL TABLE itab
Effect
If INTERNAL TABLE
is specified, the data cluster is stored in the internal
table itab
. The previous content of itab
is overwritten completely.
The first column of itab
must have the data type
s
or i
and the second column must have the type x
. Depending on the width of the
second column, the data is stored across multiple table rows if necessary. The first row contains the length occupied in the second row. The only table category allowed for itab
are
standard tables without
secondary table keys.
Notes
-
An internal table
itab
filled byEXPORT TO INTERNAL TABLE
contains exactly one data cluster. -
The content of an internal table filled by
EXPORT TO INTERNAL TABLE
can only be evaluated usingIMPORT FROM INTERNAL TABLE
for the same reasons as forEXPORT TO DATA BUFFER
. -
The variant
EXPORT TO DATA BUFFER
is preferred over the variant EXPORT TO INTERNAL TABLE because it is easier to handle. An export to an internal table is of benefit only for very large data clusters and if the available memory is almost used up. This is because its memory is requested block by block, while the memory for a string must always be completely available.
Alternative 3
... MEMORY ID id
Effect
If MEMORY
is specified, the data cluster is written in to
ABAP Memory with the ID specified in id
. id
expects a
flat
character-like data
object containing a case-sensitive ID with a maximum of 60 characters. Any existing data clusters
with the same ID id
are completely overwritten. The ID in id
identifies a data cluster in the repository and can be read again using the same identification.
Notes
- A data cluster in the ABAP memory is available to all programs within a call sequence, which makes it possible to pass data to called programs.
-
Outside of classes, an obsolete short form
exists, in which the addition
ID
can be omitted. However, this is prone to errors, since allEXPORT
statements without ID overwrite the same data cluster.
Example
Two fields with two different IDs "P1" and "P2"
with the dynamic variant of the cluster definition are written to the ABAP memory. After the statement
IMPORT
is executed, the contents of the fields text1
and text2
are swapped.
TYPES:
BEGIN OF tab_type,
para TYPE string,
dobj TYPE string,
END OF tab_type.
DATA:
id TYPE c LENGTH 10 VALUE 'TEXTS',
text1 TYPE string VALUE `IKE`,
text2 TYPE string VALUE `TINA`,
line TYPE tab_type,
itab TYPE STANDARD TABLE OF tab_type.
line-para = 'P1'.
line-dobj = 'TEXT1'.
APPEND line TO itab.
line-para = 'P2'.
line-dobj = 'TEXT2'.
APPEND line TO itab.
EXPORT (itab) TO MEMORY ID id.
IMPORT p1 = text2
p2 = text1 FROM MEMORY ID id.
Alternative 4
... DATABASE dbtab(ar) [FROM wa] [CLIENT cl] ID id
Effect
If DATABASE
is specified, the data cluster with the ID id
is stored in the database table dbtab
and saved permanently at the next
database commit. In ABAP Dictionary, the database table must be defined with a fixed
INDX-like
structure. id
expects a
flat
character-like data object containing an ID no longer than the key fields of the INDX-like table defined between the columns
RELID and SRTF2. The ID is case-sensitive.
The two-character area ar
, which must be specified directly, splits up the
rows of the database table into multiple areas, so that data clusters with the same ID id
can exist more than once in the database table.
After FROM
, a work area wa
can be specified that
must have the same data type as the database table dbtab
. In an export, the current values of the components of wa
, which are located between the fields
SRTF2 and
CLUSTR, are written to all rows occupied
by the data cluster of the database table. If the addition FROM wa
is not
specified within classes, then no data transport takes place in these database fields. If the addition
FROM wa
is not specified outside of classes, but the statement TABLES
is used to declare a
table work area for
the database table dbtab
, then, in the export, the current values of the
corresponding components of the table work area dbtab
are written to the rows of the database table.
If the database table dbtab
is client-specific, a flat character-like field cl
can be specified after the addition CLIENT
. This field contains a
client ID. If the
addition is not specified, the current client is used. The column MANDT of every row in the database table occupied by the data cluster is filled by this client ID in the export.
Notes
- Data clusters in databases are not converted when migrating from a non-Unicode database to a Unicode system. In a Unicode system, therefore, data clusters may sometimes exist that contain non-Unicode characters. These characters are automatically converted to Unicode characters in each import. When data is exported in Unicode systems, any Unicode characters in the stored data objects are saved in accordance with the relevant platform.
-
It is still possible to use a table work area implicitly (instead of using
FROM wa
explicitly). This should be considered an obsolete short form, however. -
Since each client represents a self-contained unit, the addition
CLIENT
must not be used in application programs.
Example
An internal table itab
with the name tab
and the ID "TABLE" is exported to the area "SQ"
of the database table DEMO_INDX_TABLE, filling the freely selectable components from the structure wa_indx
.
TYPES:
BEGIN OF tab_type,
col1 TYPE i,
col2 TYPE i,
END OF tab_type.
DATA:
wa_indx TYPE demo_indx_table,
wa_itab TYPE tab_type,
itab TYPE STANDARD TABLE OF tab_type.
WHILE sy-index < 100.
wa_itab-col1 = sy-index.
wa_itab-col2 = sy-index ** 2.
APPEND wa_itab TO itab.
ENDWHILE.
wa_indx-timestamp = sy-datum && sy-uzeit.
wa_indx-userid = sy-uname.
EXPORT tab = itab
TO DATABASE demo_indx_table(SQ)
FROM wa_indx
ID 'TABLE'.
Alternative 5
... SHARED MEMORY dbtab(ar) [FROM wa] [CLIENT cl] ID id
Alternative 6
... SHARED BUFFER dbtab(ar) [FROM wa] [CLIENT cl] ID id
Effect
If SHARED MEMORY
or SHARED BUFFER
is specified, the data cluster is stored in
cross-transaction application buffers of the
shared memory on the
application server. All programs of the same application server have access to these buffers.
The two application buffers differ in respect to how the system behaves when reaching the memory limit. Both application buffers can be filled to an internal maximum limit, which can be adjusted using the
profile parameter rsdb/esm/buffersize_kb
(SHARED MEMORY
) and rsdb/obj/buffersize
(SHARED BUFFER
). Before the maximum limit of the SHARED
MEMORY buffer is reached, space must be freed using the statement
DELETE FROM SHARED MEMORY
; otherwise a handleable exception is raised.
The buffer of SHARED BUFFER
is cleared automatically by a displacement when it reaches the maximum limit. This procedure deletes the least used data objects from the buffer.
When storing the data, the system creates a memory table in the application buffer. The row structure
of this table is defined using dbtab
. For dbtab
, a database table from ABAP Dictionary must be specified that has the same
structure if stored in the database table
itself. The row area ar
, the work area wa
, the
optional client cl
, and the ID id
have the same
significance for the memory table as if saved in a database table, with the exception that the length
of the ID in id
is limited to 59 or 62 characters depending on whether the addition CLIENT
is specified or not.
Notes
- When storing data in the shared memory, reference is made to a database table, even if the data is not stored in the table itself, but in an appropriately structured memory table.
- The length of the key fields of the INDX-like table addressed between the columns RELID and SRTF2 cannot exceed 59 or 62 characters, depending on whether a client column exists.
-
When data is exported, any data clusters that have the same client
cl
, row areaar
, and IDid
are overwritten. If an existing data cluster is to be overwritten by a bigger one when usingSHARED MEMORY
, and this would exceed the memory limit, then this only deletes the existing data cluster. -
Instead of saving data clusters in the shared memory, we recommend that
shared objects are used.
Shared objects enable objects with complex dependencies to be saved, can be processed like normal objects, and enable multiple users to access the shared memory without any copying effort.