I want to store hundred of millions of columns(containing id1 to id2 mappings) in the DB & at any single time, retrieve a set of about 200-500 columns based on the column names(id1) if they are in single row or using rowkeys if each column is stored in a unique row.
If I put them in a single row:- -> disadvantage is that the no of columns is quite big, that would lead to uneven load distribution,etc. -> plus factor is that I can easily read all columns I want to fetch using col names doing a single row read But if I store them each in a single row:- -> I will have to read hundreds of rows(300-500 or in rare cases up to 1000) at a single time, this may lead to bad read performance(!?). -> A bit less space efficient What schema should I go with ?
