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CREATE TABLE problems: Foreign key references.

MySQL
A foreign key should refer to a candidate key in some table. This is usually the primary key but may be a field (or list of fields) specified as UNIQUE. You must have REFERENCE permission on the table being referenced.	Execute tidy up code silently DROP TABLE t_stupid CREATE TABLE t_stupid (a INTEGER ,FOREIGN KEY(a) REFERENCES cia(population))
Specific to MySQL
It's an old tart - it will let you reference any old rubbish.