when do we use 'Collect' statement? what does 'Collect' statement do ?

[Former Member]

Hi Everyone,

Could you please help me regarding ....

When do we use 'Collect' statement? What does 'Collect' statement do ?

Thanks in advance...

[Former Member]

Hi Everyone,

Could you please help me regarding ....

When do we use 'Collect' statement? What does 'Collect' statement do ?

Thanks in advance...

[Former Member]

collect will modify the record if it exits it avoids duplication of records

The COLLECT groups all records with the same key, the key for internal table is all CHAR fields.

So in your case your table has only one char field (MATNR), so it'll be the key.

If your table was:

DATA: BEGIN OF ITAB OCCURS 0,

ZEILE LIKE MSEG-ZEILE,

MATNR LIKE MSEG-MATNR,

MENGE LIKE MSEG-MENGE,

END OF ITAB.

In this case the key is the fields ZEILE and MATNR

Message was edited by:

p498863

[former_member386202]

Hi,

This statement inserts the contents of a work area wa either as single row into an internal table itab or adds the values of its numeric components to the corresponding values of existing rows with the same key. As of Release 6.10, you can use result to set a reference to the inserted or changed row in the form of a field symbol or data reference.

Prerequisite for the use of this statement is that wa is compatible with the row type of itab and all components that are not part of the table key must have a numeric data type (i, p, f).

In standard tables that are only filled using COLLECT, the entry is determined by a temporarily created hash administration. The workload is independent of the number of entries in the table. The hash administration is temporary and is generally invalidated when the table is accessed for changing. If further COLLECT statements are entered after an invalidation, a linear search of all table rows is performed. The workload for this search increases in a linear fashion in relation to the number of entries.

In sorted tables, the entry is determined using a binary search. The workload has a logarithmic relationship to the number of entries in the table.

In hashed tables, the entry is determined using the hash administration of the table and is always independent of the number of table entries.

If no line is found with an identical key, a row is inserted as described below, and filled with the content of wa:

In standard tables the line is appended.

In sorted tables, the new line is inserted in the sort sequence of the internal table according to its key values, and the table index of subsequent rows is increased by 1.

In hashed tables, the new row is inserted into the internal table by the hash administration, according to its key values.

If the internal table already contains one or more rows with an identical key, those values of the components of work area wa that are not part of the key, are added to the corresponding components of the uppermost existing row (in the case of index tables, this is the row with the lowest table index).

The COLLECT statement sets sy-tabix to the table index of the inserted or existing row, in the case of standard tables and sorted tables, and to the value 0 in the case of hashed tables.

Outside of classes, you can omit wa INTO if the internal table has an identically-named header line itab. The statement then implicitly uses the header line as the work area.

COLLECT should only be used if you want to create an internal table that is genuinely unique or compressed. In this case, COLLECT can greatly benefit performance. If uniqueness or compression are not required, or the uniqueness is guaranteed for other reasons, the INSERT statement should be used instead.

The use of COLLECT for standard tables is obsolete. COLLECT should primarily be used for hashed tables, as these have a unique table key and a stable hash administration.

If a standard table is filled using COLLECT, it should not be edited using any other statement with the exception of MODIFY. If the latter is used with the addition TRANSPORTING, you must ensure that no key fields are changed. This is the only way to guarantee that the table entries are always unique and compressed, and that the COLLECT statement functions correctly and benefits performance. The function module ABL_TABLE_HASH_STATE can be used to check whether a standard table is suitable for editing using COLLECT.

Example

Compressed insertion of data from the database table sflight into the internal table seats_tab. The rows in which the key components carrid and connid are identical are compressed by adding the number of occupied seats to the numeric component seatsocc.

DATA: BEGIN OF seats,

carrid TYPE sflight-carrid,

connid TYPE sflight-connid,

seatsocc TYPE sflight-seatsocc,

END OF seats.

DATA seats_tab LIKE HASHED TABLE OF seats

WITH UNIQUE KEY carrid connid.

SELECT carrid connid seatsocc

FROM sflight

INTO seats.

COLLECT seats INTO seats_tab.

ENDSELECT.

Regards,

Prashant

[Former Member]

Hi,

collect statment sums up the integer field of the internal table with the same key fields and give as one record.

suppose itab contains name and number,

it contains as mary 120

mary 100

if collect statement is used then the result will be mary 220.

plzz reward points if it is useful.

[Former Member]

Hi.

Collect:

If an entry with the same key already exists, the COLLECT statement does not append a new line, but adds the contents of the numeric fields in the work area to the contents of the numeric fields in the existing entry.

COLLECT:

COLLECT is used to create unique or compressed datsets. The key fields are the default key fields of the internal table itab .

If you use only COLLECT to fill an internal table, COLLECT makes sure that the internal table does not contain two entries with the same default key fields.

If, besides its default key fields, the internal table contains number fields,the contents of these number fields are added together if the internal table already contains an entry with the same key fields.

If the default key of an internal table processed with COLLECT is blank, all the values are added up in the first table line.

If you specify wa INTO , the entry to be processed is taken from the explicitly specified work area wa . If not, it comes from the header line of the internal table itab .

After COLLECT , the system field SY-TABIX contains the index of the - existing or new - table entry with default key fields which match those of the entry to be processed.

COLLECT can create unique or compressed datasets and should be used precisely for this purpose. If uniqueness or compression are unimportant, or two values with identical default key field values could not possibly occur in your particular task, you should use APPEND instead. However, for a unique or compressed dataset which is also efficient, COLLECT is the statement to use.

If you process a table with COLLECT , you should also use COLLECT to fill it. Only by doing this can you guarantee that the internal table will actually be unique or compressed, as described above and COLLECT will run very efficiently.

If you use COLLECT with an explicitly specified work area, it must be compatible with the line type of the internal table.

COLLECT

Effect

COLLECT allows you to create unique or summarized datasets. The system first tries to find a table entry corresponding to the table key. (See also Defining Keys for Internal Tables). The key values are taken either from the header line of the internal table itab, or from the explicitly-specified work area wa. The line type of itab must be flat - that is, it cannot itself contain any internal tables. All the components that do not belong to the key must be numeric types ( ABAP Numeric Types).

If the system finds an entry, the numeric fields that are not part of the table key (see ABAPNumeric Types) are added to the sum total of the existing entries. If it does not find an entry, the system creates a new entry instead.

The way in which the system finds the entries depends on the kind of the internal table:

TYPES: BEGIN OF COMPANY,

NAME(20) TYPE C,

SALES TYPE I,

END OF COMPANY.

DATA: COMP TYPE COMPANY,

COMPTAB TYPE HASHED TABLE OF COMPANY

WITH UNIQUE KEY NAME.

COMP-NAME = 'Duck'. COMP-SALES = 10. COLLECT COMP INTO COMPTAB.

COMP-NAME = 'Tiger'. COMP-SALES = 20. COLLECT COMP INTO COMPTAB.

COMP-NAME = 'Duck'. COMP-SALES = 30. COLLECT COMP INTO COMPTAB.

Table COMPTAB now has the following contents:

NAME | SALES

-

---

Duck | 40

Tiger | 20

Regards,

Priyanka.

[Former Member]

Hi Sreenivas,

Collect statement works something like this,

It appends and adds all numeric fields.

for eg if u have a internal table itab structure like this

field1 qty1 qty2

test1 1 2

test1 2 2

test2 4 4

test5 5 5

test5 3 2

test6 2 2

test6 3 2

test6 2 4

conssider there is a table jtab with same structure.

if you use code something like this.

loop at itab.

collect itab to jtab.

endloop.

finally ur jtab will have contents like this...

jtab

field1 qty1 qty2

test1 3 4

test2 4 4

test5 8 7

test6 7 8

collect statement checks whether the contents with the same name i.e only char fields with same name.

if it exists it adds all the numeric fields correspondingly and then appends or modifies as required...

regards

Naveen