0 - 1 of 1 tags for column datatype decimal

Can you please help me concerning this matter (I didnĀ“t found it in the Teradata documentation, which is honestly little overwhelming): My table has this column -BAN DECIMAL(9,0)-, and now I want to change it to - BAN DECIMAL(15,0) COMPRESS 0.- How can I do it?

What does COMPRESS constraint 0. or any other mean anyway?