Size category

[Former Member]

Hi all,

      I came across this question from one of my senior, why SAP has given a size category in DB when SAP itself can provide the default size value as zero why they have given flexibility to the developer to set a size category, i tried to find the answers but i din't get it, can anyone please help me in providing the answer for this question...

Thanks & Regards

Faisal Pasha

[former_member187266]

Hi Faisal,

Size category reserves the specific space in DB according to the Size category.

Yes, Size category is set to zero by default, but in case of large number of entries in future for the same table, u have to increase the same if it exceeds the size reserved initially. This will result in different Small sections of data in the database.

So it is reccommended to use size category as per the requirement so that all data saved in this table are bunched together in a single section.

Thanks!!!

Ashish

[Former Member]

Hi Ashish thanks for ur answer i just want to be still more clear on this statement " This will result in different Small sections of data in the database" .

Do you mean scattering of physical memory by this statement.

Thanks and regards,

Faisal Pasha

[Former Member]

The size category is for : lets say your table is small and therefore you need size category of 7 to waste memory consumption in the backend because sap will keep huge memory for your small table .

Also if we give size category of 1 and our table is huge, the scenario in itself is incorrect. we must try to give size category greater than 1 for what our requirement is. this is the best practice.

[unknown7]

i am having the doubt if size category while i am creating db table i selected size category 1. in future no of records is more than size category i means we can change the size category in future requirements

[raymond_giuseppi]

When you create a table, the system reserves an initial amount of space in the database. If new data require more space, additional memory is added according to the size category selected.

• If you define a too small category, there will be may extents (also table spliting)
• If you define a too big category, there will be waste of space

The behavior also depends on the actual database (Oracle, Hana, etc.)

[Former Member]

thank you all....

[former_member187266]

Yes, Basically when you select any size category it has no of records against it in the display, hence, a section of database  is reserved for the same amount of records in database.

Going forward if the no. of records exceeds than the previous size category, either you have to change the size category or system itself reserves a section same as previous section which may not be adjacent to previous section.

Hence the data gets scattered between two sections than in a single bunch.

So it is always recommended to select size category as per the records needed.

If you select the size category for higher no of records even if there are no records, reserved space will not be used by other tables or records even if that is free and will not be used.

Thanks!!!