InitialD is a relational database language inspired by the tutorial D.
It is name and definition pair. name is atom, definition is (any -> boolean) function. Reltype is stored into :reltype mnesia table.
It is mnesia table, list of tuple and query of there. tuple format is {table, key, att1, att2, att3, ...}. key is a tuple of primary key of attributes or a attribute. Relval expressions are closure by itself(except relational assignment). Relval has name, types, query and keys.
It is mnesia table. It is variable. Relval has name, types, query and keys.
It is virtual structure for Relval literal. Reltuple has name, types, and body.