topic control brek statements in Application Development and Automation Discussions

control brek statements

Former Member — Fri, 16 Feb 2007 09:58:43 GMT

using At first

At new

At end of

At last

send me one example program

byee

Re: control brek statements

Former Member — Fri, 16 Feb 2007 10:01:05 GMT

AT - Control break with internal tables

Variants

1. AT NEW f.

2. AT END OF f.

3. AT FIRST.

4. AT LAST.

Effect

In a LOOP which processes a dataset created with EXTRACT , you can use special control structures for control break processing. All these structures begin with AT and end with ENDAT . The sequence of statements which lies between them is then executed if a control break occurs.

You can use these key words for control break processing with extract datasets only if the active LOOP statement is proceesing an extract dataset.

The control level structure with extract datasets is dynamic. It corresponds exactly to the sort key of the extract dataset, i.e. to the order of fields in the field group HEADER by which the extract dataset was sorted .

At the start of a new control level (i.e. immediately after AT ), the following occurs in the output area of the current LOOP statement:

All default key fields (on the right) are filled with "*" after the current control level key.

All other fields (on the right) are set to their initial values after the current control level key.

Between AT and ENDAT , you can use SUM to insert the appropriate control totals in the number fields (see also ABAP/4 number types ) of the LOOP output area (on the right) after the current control level key. Summing is supported both at the beginning of a control level ( AT FIRST , AT NEW f ) and also the end of a control level ( AT END OF f , AT LAST ).

At the end of the control level processing (i.e. after ENDAT ), the old contents of the LOOP output area are restored.

Notes

When calculating totals, you must ensure that the totals are inserted into the same sub-fields of the LOOP output area as those where the single values otherwise occur. If there is an overflow, processing terminates with a runtime error.

If an internal table is processed only in a restricted form (using the additions FROM , TO and/or WHERE with the LOOP statement), you should not use the control structures for control level processing because the interaction of a restricted LOOP with the AT statement is currenly not properly defined.

With LOOP s on extracts, there are also special control break control structures you can use.

Note

Runtime errors

SUM_OVERFLOW : Overflow when calculating totals with SUM .

Variant 1

AT NEW f.

Variant 2

AT END OF f.

Effect

f is a sub-field of an internal table processed with LOOP . The sequence of statements which follow it is executed if the sub-field f or a sub-field in the current LOOP line defined (on the left) before f has a differnt value than in the preceding ( AT NEW ) or subsequent ( AT END OF ) table line.

Example

DATA: BEGIN OF COMPANIES OCCURS 20,

NAME(30),

PRODUCT(20),

SALES TYPE I,

END OF COMPANIES.

...

LOOP AT COMPANIES.

AT NEW NAME.

NEW-PAGE.

WRITE / COMPANIES-NAME.

ENDAT.

WRITE: / COMPANIES-PRODUCT, COMPANIES-SALES.

AT END OF NAME.

SUM.

WRITE: / COMPANIES-NAME, COMPANIES-SALES.

ENDAT.

ENDLOOP.

The AT statements refer to the field COMPANIES-NAME .

Notes

If a control break criterion is not known until runtime, you can use AT NEW (name) or AT END OF (name) to specify it dynamically as the contents of the field name . If name is blank at runtime, the control break criterion is ignored and the sequence of statements is not executed. If name contains an invalid component name, a runtime error occurs.

By defining an offset and/or length, you can further restrict control break criteria - regardless of whether they are specified statically or dynamically.

A field symbol pointing to the LOOP output area can also be used as a dynamic control break criterion. If the field symbol does not point to the LOOP output area, a runtime error occurs.

Note

Runtime errors

AT_BAD_PARTIAL_FIELD_ACCESS : Invalid sub-field access when dynamically specifying the control break criterion.

AT_ITAB_FIELD_INVALID : When dynamically specifying the control break criterion via a field symbol, the field symbol does not point to the LOOP output area.

ITAB_ILLEGAL_COMPONENT : When dynamically specifying the control break criterion via (name) the field name does not contain a valid sub-field name.

Variant 3

AT FIRST.

Variant 4

AT LAST.

Effect

Executes the appropriate sequence of statements once during the first ( AT FIRST ) or last ( AT LAST ) loop pass.

Example

DATA: BEGIN OF COMPANIES OCCURS 20,

NAME(30),

PRODUCT(20),

SALES TYPE I,

END OF COMPANIES.

...

LOOP AT COMPANIES.

AT FIRST.

SUM.

WRITE: 'Sum of all SALES:',

55 COMPANIES-SALES.

ENDAT.

WRITE: / COMPANIES-NAME, COMPANIES-PRODUCT,

55 COMPANIES-SALES.

ENDLOOP.

http://www.sts.tu-harburg.de/teaching/sap_r3/ABAP4/at_itab.htm

Re: control brek statements

Former Member — Fri, 16 Feb 2007 10:01:39 GMT

Check

http://help.sap.com/saphelp_erp2005vp/helpdata/en/9f/db9f1f35c111d1829f0000e829fbfe/frameset.htm

Regards,

Santosh

Re: control brek statements

sreeramkumar_madisetty — Fri, 16 Feb 2007 10:03:58 GMT

go through the link.

http://www.sts.tu-harburg.de/teaching/sap_r3/ABAP4/at_itab.htm

Regards,

kumar

Re: control brek statements

Former Member — Fri, 16 Feb 2007 10:05:53 GMT

Hello,

This is from SAP, or refer the link http://help.sap.com/saphelp_erp2005vp/helpdata/en/9f/db9f1f35c111d1829f0000e829fbfe/frameset.htm

1. AT NEW f.

2. AT END OF f.

3. AT FIRST.

4. AT LAST.

5. AT fg.

Effect

In a LOOP which processes a dataset created with EXTRACT, you can use special control structures for control break processing. All these structures begin with AT and end with ENDAT. The sequence of statements which lies between is executed whenever a control break occurs.

You can use these key words for control break processing with extract datasets only if the active LOOP statement is processing an extract dataset.

At the end of a control group ( AT END OF, AT LAST), there are two types of control level information between AT and ENDAT:

If the sort key of the extract dataset contains a non-numeric field h (particularly in the field group HEADER), the field CNT(h) contains the number of control breaks in the (subordinate) control level h.

For extracted number fields g (see also ABAP Number Types), the fields SUM(g) contain the relevant control totals.

Notes

The fields CNT(h) and SUM(g) can only be addressed after they have been sorted. Otherwise, a runtime error may occur.

The fields CNT(h) and SUM(g) are filled with the relevant values for a control level at the end of each control group ( AT END OF, AT LAST), not at the beginning (AT FIRST, AT NEW).

When calculating totals with SUM(g), the system automatically chooses the maximum field sizes so that an overflow occurs only if the absolute value area limits are exceeded.

You can also use special control break control structures with LOOPs on internal tables.

Variant 1

AT NEW f.

Variant 2

AT END OF f.

Effect

f is a field from the field group HEADER. The enclosed sequence of statements is executed if the field f occurs in the sort key of the extract dataset (and thus also in the field group HEADER) and the field f or a superior sort criterion has a different value in the current LOOP line than in the preceding (AT NEW) or subsequent (AT END OF) record of the extract dataset.

If f is not an assigned field symbol, the control break criterion is ignored, and the subsequent sequence of statements is not executed. If a field symbol is assigned, but does not point to the HEADER field group, the system triggers a runtime error.

Example

DATA: NAME(30),

SALES TYPE I.

FIELD-GROUPS: HEADER, INFOS.

INSERT: NAME INTO HEADER,

SALES INTO INFOS.

...

LOOP.

AT NEW NAME.

NEW-PAGE.

ENDAT.

...

AT END OF NAME.

WRITE: / NAME, SUM(SALES).

ENDAT.

ENDLOOP.

Notes

If the extract dataset is not sorted before processing with LOOP, no control level structure is defined and the statements following AT NEW or AT END OF are not executed.

Fields which stand at hex zero are ignored by the control break check with AT NEW or AT END OF. This corresponds to the behavior of the SORT statement, which always places unoccupied fields (i.e. fields which stand at hex zero) before all occupied fields when sorting extract datasets, regardless of whether the sort sequence is in ascending or descending order.

Variant 3

AT FIRST.

Variant 4

AT LAST.

Effect

Executes the relevant series of statements just once - either on the first loop pass (with AT FIRST) or on the last loop pass (with AT LAST).

Variant 5

AT fg.

Addition:

... WITH fg1

Effect

This statement makes single record processing dependent on the type of extracted record.

The sequence of statements following AT fg are executed whenever the current LOOP record is created with EXTRACT fg (in other words: when the current record is a fg record).

Addition

... WITH fg1

Effect

Executes the sequence of statements belonging to AT fg WITH fg1 only if the record of the field group fg in the dataset is immediately followed by a record of the field group fg1.

Regs,

Venkat Ramanan N

Message was edited by:

Venkat Ramanan Natarajan

Re: control brek statements

Former Member — Fri, 16 Feb 2007 10:08:36 GMT

Have a look at below link and go to page 300 - Control level processing. It will surely help you to undersatnd the same.

http://help.sap.com/printdocu/core/Print46c/en/data/pdf/BCABA/BCABA.pdf

I hope it helps.

Best Regards,

Vibha

*Please mark all the helpful answers

Re: control brek statements

prabhu_s2 — Fri, 16 Feb 2007 10:09:58 GMT

hi samara

okie for undersatnding purpose consider ur internal table of 3 fields

a b c

1 2 2

1 2 3

at first

gets triggered for the first itegration of the loop

At new c

first new val of 2 seen and this is triggered. in the second line item the same value and no trigger of this stmt and in third a new value seen and hence a trigger seen

at last

executes at the end of the loop only

At end of c

works in similar fashion like atnew. but here it happends only the the end of the identical record (sorted)

Re: control brek statements

Former Member — Fri, 16 Feb 2007 10:14:41 GMT

REPORT zex36 .

DATA: BEGIN OF it OCCURS 4,

f1,

f2,

END OF it.

it = '1A'. APPEND it.

it = '3A'. APPEND it.

it = '1B'. APPEND it.

it = '2B'. APPEND it.

SORT it BY f1.

LOOP AT it.

AT FIRST.

WRITE: / 'AT FIRST IS TRIGGERED NOW'.

ULINE.

ENDAT.

AT NEW f1.

WRITE: / 'start of:', it-f1.

ENDAT.

WRITE: /4 it-f1.

AT END OF f1.

WRITE: / 'end of:', it-f1.

WRITE : /.

ENDAT.

AT LAST.

ULINE.

WRITE : / 'AT LAST IS TRIGGERED NOW'.

ULINE.

ENDAT.

ENDLOOP.

FREE it.