This package contains the query-evaluation components of the database. Query
evaluation includes the following kinds of statements:
- SELECT statements
- INSERT statements
- UPDATE statements
- DELETE statements
In fact, the only real difference with any of these statements is what is done
with the rows that are retrieved.
Commands that drive the evaluation components are represented as the
{@link edu.caltech.nanodb.commands.QueryCommand} class and its subclasses. The
details of the commands being performed are filled in by the SQL parser.