Difference between a schema and a database in db2
This simple question has caused an unusual amount of debate, and I feel compelled to quote an authoritative source.

The database stores all data in tables that are related to one another. Relationships are established between tables such that data is shared and duplication is minimized.
A table space is a storage structure containing tables, indexes, large objects, and long data. They are used to organize data in a database into logical storage groupings that relate to where data is stored on a system.
A schema is a collection of named objects; it provides a way to group those objects logically. A schema is also a name qualifier; it provides a way to use the same natural name for several objects, and to prevent ambiguous references to those objects.