Question

I am trying to create table with division possibilities and i want that the sum of all the cells in one row will be 1.
For example:

0.1, 0.2, 0.3, 0.3, 0.1  

Answer 1

You can create a constraint on the table that requires each row to meet some condition, in this case that total of columns be 1:

create table my_table (
  col1 number,
  col2 number,
  col3 number,
  col4 number,
  constraint assert_sum_is_one check (col1 + col2 + col3 + col4 = 1)
)

Any attempt to insert or update rows to not total 1 will cause a constraint violation exception.