how to join two tables

[Former Member]

hi

how to join two tables using inner join if the first table has two primary keys and second table has 3 primary keys

[Former Member]

hi

how to join two tables using inner join if the first table has two primary keys and second table has 3 primary keys

[Former Member]

Would describe type of joins in ABAP, which might differ with other joins.

The join syntax represents a recursively nestable join expression. A join expression consists of a left-hand and a right- hand side, which are joined either by means of INNER JOIN or LEFT OUTER JOIN. Depending on the type of join, a join expression can be either an inner (INNER) or an outer (LEFT OUTER) join. Every join expression can be enclosed in round brackets. If a join expression is used, the SELECT command circumvents SAP buffering.

On the left-hand side, either a single database table, a view dbtab_left, or a join expression join can be specified. On the right-hand side, a single database table or a view dbtab_right as well as join conditions join_cond can be specified after ON. In this way, a maximum of 24 join expressions that join 25 database tables or views with each other can be specified after FROM.

AS can be used to specify an alternative table name tabalias for each of the specified database table names or for every view. A database table or a view can occur multiple times within a join expression and, in this case, have various alternative names.

The syntax of the join conditions join_cond is the same as that of the sql_cond conditions after the addition WHERE, with the following differences:

At least one comparison must be specified after ON.

Individual comparisons may be joined using AND only.

All comparisons must contain a column in the database table or the view dbtab_right on the right-hand side as an operand.

The following additions not be used: NOT, LIKE, IN.

No sub-queries may be used.

For outer joins, only equality comparisons (=, EQ) are possible.

If an outer join occurs after FROM, the join condition of every join expression must contain at least one comparison between columns on the left-hand and the right-hand side.

In outer joins, all comparisons that contain columns as operands in the database table or the view dbtab_right on the right-hand side must be specified in the corresponding join condition. In the WHERE condition of the same SELECT command, these columns are not allowed as operands.

Resulting set for inner join

The inner join joins the columns of every selected line on the left- hand side with the columns of all lines on the right-hand side that jointly fulfil the join_cond condition. A line in the resulting set is created for every such line on the right-hand side. The content of the column on the left-hand side may be duplicated in this case. If none of the lines on the right-hand side fulfils the join_cond condition, no line is created in the resulting set.

Resulting set for outer join

The outer join basically creates the same resulting set as the inner join, with the difference that at least one line is created in the resulting set for every selected line on the left-hand side, even if no line on the right-hand side fulfils the join_cond condition. The columns on the right-hand side that do not fulfil the join_cond condition are filled with null values.

Note

If the same column name occurs in several database tables in a join expression, they have to be identified in all remaining additions of the SELECT statement by using the column selector ~.

Example

Join the columns carrname, connid, fldate of the database tables scarr, spfli and sflight by means of two inner joins. A list is created of the flights from p_cityfr to p_cityto. Alternative names are used for every table.

PARAMETERS: p_cityfr TYPE spfli-cityfrom,

p_cityto TYPE spfli-cityto.

DATA: BEGIN OF wa,

fldate TYPE sflight-fldate,

carrname TYPE scarr-carrname,

connid TYPE spfli-connid,

END OF wa.

DATA itab LIKE SORTED TABLE OF wa

WITH UNIQUE KEY fldate carrname connid.

SELECT c_{carrname p}connid f~fldate

INTO CORRESPONDING FIELDS OF TABLE itab

FROM ( ( scarr AS c

INNER JOIN spfli AS p ON p_{carrid = c}carrid

AND p~cityfrom = p_cityfr

AND p~cityto = p_cityto )

INNER JOIN sflight AS f ON f_{carrid = p}carrid

AND f_{connid = p}connid ).

LOOP AT itab INTO wa.

WRITE: / wa-fldate, wa-carrname, wa-connid.

ENDLOOP.

Example

Join the columns carrid, carrname and connid of the database tables scarr and spfli using an outer join. The column connid is set to the null value for all flights that do not fly from p_cityfr. This null value is then converted to the appropriate initial value when it is transferred to the assigned data object. The LOOP returns all airlines that do not fly from p_cityfr.

PARAMETERS p_cityfr TYPE spfli-cityfrom.

DATA: BEGIN OF wa,

carrid TYPE scarr-carrid,

carrname TYPE scarr-carrname,

connid TYPE spfli-connid,

END OF wa,

itab LIKE SORTED TABLE OF wa

WITH NON-UNIQUE KEY carrid.

SELECT s_{carrid s}carrname p~connid

INTO CORRESPONDING FIELDS OF TABLE itab

FROM scarr AS s

LEFT OUTER JOIN spfli AS p ON s_{carrid = p}carrid

AND p~cityfrom = p_cityfr.

LOOP AT itab INTO wa.

IF wa-connid = '0000'.

WRITE: / wa-carrid, wa-carrname.

ENDIF.

ENDLOOP.

[Former Member]

Hi,

u don't need to have equal number of primary keys.

DATA: BEGIN OF wa,
        carrid TYPE spfli-carrid,
        connid TYPE spfli-connid,
        fldate TYPE sflight-fldate,
        bookid TYPE sbook-bookid,
      END OF wa,
      itab LIKE SORTED TABLE OF wa
                WITH UNIQUE KEY carrid connid fldate bookid.

SELECT  p~carrid p~connid f~fldate b~bookid
  INTO  CORRESPONDING FIELDS OF TABLE itab
  FROM  ( ( spfli AS p
            INNER JOIN sflight AS f ON p~carrid = f~carrid AND
                                       p~connid = f~connid    )
            INNER JOIN sbook   AS b ON b~carrid = f~carrid AND
                                       b~connid = f~connid AND
                                       b~fldate = f~fldate     )
  WHERE p~cityfrom = 'FRANKFURT' AND
        p~cityto   = 'NEW YORK'  AND
        f~seatsmax > f~seatsocc.

LOOP AT itab INTO wa.
  AT NEW fldate.
    WRITE: / wa-carrid, wa-connid, wa-fldate.
ENDAT.
  WRITE / wa-bookid.
ENDLOOP.

rgds,

bharat.

[Former Member]

Hi,

Check the following link:

http://www.sap-img.com/abap/select-statement-with-inner-join-is-taking-forever.htm

Regards,

Bhaskar

[vinod_vemuru2]

Hi Jyothsna,

There is no restriction for the number of primary keys in the jion tables. But there should be at least one common field between the tables.

Check the example below.

SELECT a_{vbeln b}posnr b~matnr

INTO TABLE i_delivery

FROM likp AS a INNER JOIN lips AS b

ON a_{vbeln EQ b}vbeln

WHERE a~vbeln IN so_vbeln

AND b~matnr IN so_matnr.

Here likp has one key field. Lips has 2. But there is a common field vbeln.

Thanks,

vinod.

[ak_upadhyay]

Hi,

Check this....

*&---------------------------------------------------------------------*
*& Report  YPRO_2                                                      *
*&                                                                     *
*&---------------------------------------------------------------------*
*&                                                                     *
*&                                                                     *
*&---------------------------------------------------------------------*

REPORT  YPRO_2                                  .

TABLES: VBAP , MAKT.

SELECT-OPTIONS: A_MATNR FOR VBAP-MATNR.

DATA:   BEGIN OF IT OCCURS 0,

        VBELN LIKE VBAP-VBELN,
        POSNR LIKE VBAP-POSNR,
        MATNR LIKE VBAP-MATNR,
        MAKTX LIKE MAKT-MAKTX,
        END OF IT.

       SELECT
       VBAP~VBELN
       VBAP~POSNR
       VBAP~MATNR
       MAKT~MAKTX
       INTO TABLE IT FROM VBAP INNER JOIN MAKT ON VBAP~MATNR =
       MAKT~MATNR WHERE VBAP~MATNR IN A_MATNR.

LOOP AT IT.

 WRITE:/ IT-VBELN, IT-POSNR, IT-MATNR, IT-MAKTX.

 ENDLOOP.

Reward points if useful....

Regards

AK