is it a structure or an internal table?

TYPES: BEGIN OF PPP
        ------
       END OF PPP,

   xxx TYPE STANDARD TABLE OF PPP

My questi开发者_如何转开发on is will xxx be an internal table or a structure?

it will be an internal table. its lines will be of the type PPP.

DATA: xxx TYPE STANDARD TABLE OF PPP, "produces table with lines of type ppp
      yyy type PPP.                    "produces flat structure of type ppp. 

yyy is a structure of type PPP and can be appended to xxx since they are of the same type.

TYPES: BEGIN OF PPP
    ------
   END OF PPP,

xxx TYPE STANDARD TABLE OF PPP

xxx won't be either a structure or an internal table, but a table type.

If you declare:

DATA: lt_xxx TYPE xxx.

Then you would have a standard internal table with its structure based on PPP structure definition (since xxx is a table tabe based on PPP).

Here XXX will be the internal table - that hold the structure of PPP

Paulo is right;

xxx won't be either a structure or an internal table, but a table type.

Or you can create Structure or Internal Table with statement below:

DATA: ls_xxx  TYPE ppp. " <<-- Structure
DATA: lt_xxx  TYPE STANDARD TABLE OF ppp. " <<-- Internal Table
DATA: lt_xxx2 TYPE xxx. " <<-- Internal Table