ABAP READ TABLE INDEX Statement syntax, information and example SAP source code

READ TABLE - index

Short Reference

ABAP Syntax ... INDEX idx [USING KEY keyname
] ... .

ABAP_ADDITION:
... USING KEY keyname

What does it do? If the INDEX addition is used, the READ statement reads the row of the row number specified in idx with respect to a table index. idx is a numerical expression position
of the operand type i . If the value of idx is less than or equal to 0 or greater than the number of table rows, no row is read and sy-subrc is set to 4. If the read is successful, the system field sy-tabix contains the row number specified in idx in the primary or secondary table index used.
If the addition USING KEY is not used, the addition INDEX
can only be specified for index tables
and determines the row to be read from the primary table index .
Latest notes: Table expressions enable reads to be performed in operand positions too. Here an index is specified as a numeric argument idx
.

Example ABAP Coding Reads the first ten rows of the internal table
sflight_tab using the primary table index. Instead of the DO loop, the LOOP loop can normally also be used to do this.
DATA: sflight_tab TYPE SORTED TABLE OF sflight
WITH NON-UNIQUE KEY seatsocc,
sflight_wa LIKE LINE OF sflight_tab.

...

SELECT *
FROM sflight
INTO TABLE sflight_tab
WHERE carrid = 'LH' AND
connid = '400'.

...

DO 10 TIMES.
READ TABLE sflight_tab INDEX sy-index INTO sflight_wa.
IF sy-subrc <(><<)>> 0.
EXIT.
ENDIF.
...
ENDDO.

ABAP_ADDITION ... USING KEY keyname

What does it do? If the addition USING KEY is used, a table key can be declared in keyname to declare the table index to be used explicitly.
If the table has a sorted secondary key , this can be specified in keyname . The row to be read is then determined from its secondary table index . You cannot declare a secondary hashed key .
If the primary table key is specified under the name primary_key , the table must be an index table, and the behavior is the same as when USING KEY is not specified.
Latest notes: If a sorted secondary key exists, the INDEX addition can be used for all table types, if USING KEY is used.
Table expressions enable reads to be performed in operand positions too. The table key for an index is specified using KEY keyname INDEX
.

Example ABAP Coding Reads the first ten rows of the internal table
sflight_tab using a secondary table index. Instead of the DO loop, the LOOP loop can also be used to do this.
DATA: sflight_tab TYPE HASHED TABLE OF sflight
WITH UNIQUE KEY primary_key
COMPONENTS carrid connid fldate
WITH NON-UNIQUE SORTED KEY occupied_seats
COMPONENTS seatsocc,
sflight_wa LIKE LINE OF sflight_tab.

...

SELECT *
FROM sflight
INTO TABLE sflight_tab
WHERE carrid = 'LH' AND
connid = '400'.

...

DO 10 TIMES.
READ TABLE sflight_tab
INDEX sy-index USING KEY occupied_seats
INTO sflight_wa.
IF sy-subrc <(><<)>> 0.
EXIT.
ENDIF.
...
ENDDO.

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