DATABASE

### Message Hash Version 1
__import__(hashlib).md5().hexdigest()

### Feed Hash Version 1
__import__(hashlib).md5(message.title+u"\u9256"+message.summary).hexdigest()

### DB Vesrion 1

CREATE TABLE meta (
    version int);

INSERT INTO "meta" VALUES(1);

CREATE TABLE feeds (
    id int PRIMARY KEY,
    version int,
    hash VARCHAR(32),
    UNIQUE(version, hash)
    );

CREATE TABLE messages (
    feed int,
    version int,
    hash VARCHAR(32),
    ctime DATETIME,
    FOREIGN KEY(feed) REFERENCES feeds(id),
    PRIMARY KEY(feed, version, hash));

### Feed Hash Version 0
hash(feed['url'])

### Message Hash Version 0
hash(message.title) ^ hash(message.summary)

### DB Version 0

CREATE TABLE feeds (
    id int PRIMARY KEY,
    version int,
    hash int,
    UNIQUE(version, hash)
    );

CREATE TABLE messages (
    feed int,
    version int,
    hash int,
    ctime datetime,
    FOREIGN KEY(feed) REFERENCES feeds(id),
    PROMARY KEY(feed, version, hash)
    );