Basic ABAP queries

[Former Member]

Hi,

I am new to ABAP...kindly answer these queries...

1>Why Loop at doesnot work for windows other than MAIN in sap scripts ?

2>What is the best way to inner join multiple database(more than 6 or 7) tables? is there any direct method to inner join internal tables ?

3> Why do we have to activate ?? In which scenarios is activation not requried .

[andrea_galluccio2]

Hi,

try to answer to your questions .

1>Why Loop at doesnot work for windows other than MAIN in sap scripts ?

Loop instruction, is called in the program that commands the sapscript (the control program). So in script u declare an element to print on the form, and in the control program, u give the instruction (with a particular CALL FUNCTION) to print it.

The MAIN window is different from other kind of windows because is able to resize itself depends on how elements u print in it: more elements you print, more MAIN window will be big on the page. The other windows have a standard size.

2>What is the best way to inner join multiple database(more than 6 or 7) tables? is there any direct method to inner join internal tables ?

Usually, u can use nested select clausole for example:

select * from vbak where

select * from vbap where vbeln = vbak-vbeln ...

endselect.

endselect.

Or u can use "inner join" instruction for example

select * from vbak as a

inner join vbap as b

on a~vbeln = b~vbeln....

endselect.

Or u can use internal tables with select

select * from vbak into table ivbak.

loop at ivabk.

select * from vbap where vbeln = ivbak-vbeln.

..

endloop.

endselect.

Usually, is the programmer that decide what is the best way to perform the selection based on the business requirements.

3> Why do we have to activate ?? In which scenarios is activation not requried .

Activation is ALWAYS necessary and implies saving data.

Each object in SAP must be activated. Development packages (like $tmp for example), not requiring the activation process.

Hope it helps.

Bye

Andrea

Pls reward if it helps

[Former Member]

Hi,

Thanks for the reply ...its of great help..however addtional

doubts rise...

1> is there ne direct way to inner join two internal tables ?

(as we cant use inner join on two internal with select statement and even for using for all enteries, atleast one database table is required )

2> is activation just a mere combination of save and check ??

[Former Member]

> Hi,

>

> Thanks for the reply ...its of great help..however

> addtional

> doubts rise...

>

> 1> is there ne direct way to inner join two internal

> tables ?

> (as we cant use inner join on two internal with

> select statement and even for using for all enteries,

> atleast one database table is required )

>

No you cannnot join the internal tables the way you do the database tables.

>

> 2> is activation just a mere combination of save and

> check ??

It also compiles the code converts that into executable format internally.

Regards,

Ravi

[Former Member]

hi,

3) After coding, we should Activate because during Activation, the system creates a Run Time object. When we execute, the system executes this Run Time Object.

REgards,

Sailaja.

[Former Member]

Hi,

Thanks Andrea ,Sailaja and Ravi ..thanks for the reply ..

I am not able to put rewards points for you guys..it says some forum error...

Ravi ,

Then watz the best way to inner join two internal tables ...other than looping wrt one table and using read statement on other....

[Former Member]

That is the best option available, you don't have a choice. You can use SORTED / HASHED tables, so that the performance impact will not be there.

Regards,

Ravi