Determine sap table size via program RSTABLESIZE

• Go to Transaction code SE38 and Enter the program name as RSTABLESIZE, Execute.

• Enter the Table name and click on execute.

• Output.

Type Group

• A type group/pool is sort of like an INCLUDE program which you use to put all of  your TYPES statements into, mostly it is used for reuse, so you define your TYPES there, and they can be included in any program, or class, and be used within.
• Ex : SLIS , ABAP
• SLIS.

• ABAP

• To use them in program we use key word ‘TYPE-POOLS’.
• It allows us to define non-predefined types. 
• Combination of all such non-predefined types is knows as type-pool or type-group. 
• In simple terms, if we want to use some custom types in various programs then we need not define them separately, we can simply create a type group in ABAP dictionary and use that in our programs.

Steps

• Go to transaction code : SE11.

• Click on Type-Group radio button.

• Enter the type-group name start's with Y or Z<Type-group name> and click on create.

• Enter short description and required types , constants.

Note : Variable's name must start with <Type group name>_.

                  more information....................

Appending Structure to the Customized Table /Standard Table

• Append  is used to append a structure at end of table.
• Go to Transaction Code : SE11.

• Enter the customized Table name and click on change button  .

• Table looks like,

• Click on Append Structure.

• Click on Yes.

• Pop-up will appear.

• Enter the structure name start's with Y or Z<Structure name > and click on continue.

• Enter the short description.

• Enter the short description.

• Enter the required fields in structure.

• Click on Utilities -> Enhancement Category.

• Click on continue.

• Select the required enhancement category and click on copy button.

• Save ->Check->Activate the structure.

• Click on Back button.

• Save -> Check -> activate the table.

                                        more information...................

Including Structure to the Customized Table

• Go to Transaction Code : SE11.

• Enter the customized Table name and click on change button  .

• Table looks like,

Include

• Include keyword is used to insert a structure between the table fields.

Steps

• Create a Structure.

• Select the table field where do you want to insert a structure.

• Click on insert row.

• A will be inserted.

• Enter ".include" .

• Enter the structure name as Data Element.

• Press Enter.

• Save -> Check -> Activate.

                                                 more information.............

Deep Structure

• Table type within a structure is called as Deep structure.

Steps

• Create a Structure.

• Create a Table Type.

• Enter the component name.

• In component type enter the Table type name and press Enter.

• Save->Check->Activate.

more information..................

Table Type

• Table Type is a just structure of Table which contains rows and columns.

Creation of Table Type

Steps

• Either we can create a structure or we can take table structure.

Table Type

• Go to Transaction code SE11.

• Select Data type radio button.

• Enter table type name start's with Y or Z<Table Type name>.

• Click on create button.

• Select Table Type radio button .

• Click on continue.

• Enter the short description.

• Enter the Line Type as either structure name or table structure name and press Enter.

• Save -> Check -> Activate.

                                            more information...................