MySQL and NoSQL: Help me to choose the right one

Question

There is a big database, 1,000,000,000 rows, called threads (these threads actually exist, I\'m not making things harder just because of I enjoy it). Threads has only a few

Answer 1

Indices are a must - but remember to choose the right type of index: BTREE is more suitable when using queries with "<" or ">" in your WHERE clauses, while HASH is more suitable when you have many distinct values in one column and you are using "=" or "<=>" in your WHERE clause.

Further reading http://dev.mysql.com/doc/refman/5.0/en/mysql-indexes.html