notes varchar,
cred blob,
prev blob,
+ tag varchar,
PRIMARY KEY (id,type,expires)
);
CREATE INDEX cred_ns ON cred(ns);
memo varchar, // Description
start timestamp, // When it should take effect
expires timestamp, // When not longer valid
+ target_key varchar, // Item Key (or 2nd key, assuming user is first)
+ target_date timestamp, // Item's relevant date/stamp
construct blob, // How to construct this object (like History)
PRIMARY KEY(id)
);