Referential integrity: it was not allowed to delete a row with NULL in the parent table, if there was a row with NULL in the child table.

CREATE VIEW now supports the OR REPLACE clause

When creating functions within a schema, those functions could not be used in views, nested queries, and constraints.

Experimental feature to support case sensitive catalog names and database names using the DATABASE() method.

When creating functions within a schema, those functions could not be used in views, nested queries, and constraints.