Hi Wouldn't this make it impossible to rename the tag without also renaming all entries in "feed_tag"? Say for instance if you want to rename your "My hobbies" tag to "Hobbies" at some point?
Cheers, Svenn-Arne On Thu 02 May 2013 06:30:42 PM CEST, Riccardo Padovani wrote: > On Thu, May 2, 2013 at 4:40 PM, Joey Chan <[email protected]> wrote: >> Hi Ladies and Gentlemen, > > Hi :) > >> SQL code is generated from the physical diagram, pls check below: >> >> [snip] >> >> 4. table tag: store data of tag; > > Why in table tag there is an ID and the name can be NULL? > In my opinion is better to modify the tag's table in this way: > > CREATE TABLE tag ( > name VARCHAR(99) NOT NULL PRIMARY KEY > ); > > This because two tags can't have the same name, and a tag can't have > NULL as name. > Accordingly to this, feed_tag has to be: > > CREATE TABLE feed_tag ( > id INTEGER NOT NULL PRIMARY KEY AUTOINCREMENT, > feed_id INTEGER NULL, > tag_name VARCHAR(99) NULL, > FOREIGN KEY(feed_id) REFERENCES feed(id) on delete cascade > ); > > What do you think of what I said? > -- > Riccardo Padovani <[email protected]> > -- Mailing list: https://launchpad.net/~ubuntu-touch-coreapps Post to : [email protected] Unsubscribe : https://launchpad.net/~ubuntu-touch-coreapps More help : https://help.launchpad.net/ListHelp
