ddevaudre...@intellicare.com wrote:
> PJ wrote on 02/10/2009 12:44:04 PM:
>
>
>> -- -
>> -- Table `books`
>> -- -
>> CREATE TABLE IF NOT EXISTS `books` (
>> `id` SMALLINT(4) UNSIGNED NOT N
PJ wrote on 02/10/2009 12:44:04 PM:
> -- -
> -- Table `books`
> -- -
> CREATE TABLE IF NOT EXISTS `books` (
> `id` SMALLINT(4) UNSIGNED NOT NULL AUTO_INCREMENT ,
> `title` VARCHAR(148) NU
PJ
PB>Engine choice is another issue. InnoDB properly isolates FK
enforcement in the database. The MyISAM tradeoff (for speed) is that
you have to implement FK logic in code.
PJ>Forgive my naiveté, but how do you do that?
You write application code to implement the equivalent of ON DELETE
Peter Brawley wrote:
> PJ
>
> >But what about foreign keys? Don't I need that to find the relationships
> >between the books, the authors and the categories? After all, isn't this
> >a relational db? If so, I can't use the default engine (MyISAM) which
> >does not support FK. So, if I have to use f
PJ
>But what about foreign keys? Don't I need that to find the relationships
>between the books, the authors and the categories? After all, isn't this
>a relational db? If so, I can't use the default engine (MyISAM) which
>does not support FK. So, if I have to use foreign keys, I have to change
>
Peter Brawley wrote:
> PJ,
> As I understand it, I have one table "books" it lists all the info for
> the book other than the author(s) or the categories ; for these I need
> an authors table and a category table... I'll continue with the authors
> as categories will surely be the same thing.
>
> >
PJ,
As I understand it, I have one table "books" it lists all the info for
the book other than the author(s) or the categories ; for these I need
an authors table and a category table... I'll continue with the authors
as categories will surely be the same thing.
>BTW, I cannot use ISBN as
>PK sin
Book table:
book id : 1, name: some book name
Author table
Author id: 1, name: author 1
Author id: 2, name: author 2
Rel_author_book table:
Book id: 1, author id: 1
Book id: 1, author id: 2
Same with categories and other 1:N relations
Olaf
On 2/9/09 2:01 PM, "PJ" wrote:
> Peter Brawley
Peter Brawley wrote:
> PJ
>
>> Why do I need a third table?
>
> The clue is "author (could be 2 or more)" in your books column list.
> It is incorrect to store two author names or IDs in one column. The
> relationship is 1:many. So you need a bridge table:
>
> books(id PK, etc...)
> authors(id PK,
See normalization...
You don't need to do this but it is considered good practice for many
reasons
On 2/9/09 12:04 PM, "Peter Brawley" wrote:
> PJ
>
>> Why do I need a third table?
>
> The clue is "author (could be 2 or more)" in your books column list. It
> is incorrect to store two author
PJ
Why do I need a third table?
The clue is "author (could be 2 or more)" in your books column list. It
is incorrect to store two author names or IDs in one column. The
relationship is 1:many. So you need a bridge table:
books(id PK, etc...)
authors(id PK, etc...)
books_authors(id PK, bid
Olaf Stein wrote:
> Just about the authors
>
> You need a separate table for them and then an table linking authors and
> books.
>
>
You lose me here... :-(
Why do I need a third table?
I may have 2 or three books with 3 authors, quite a few with 2 authors
and many with just 1 author.
I can't se
Just about the authors
You need a separate table for them and then an table linking authors and
books.
So you have table books, authors and rel_books_authors where rel_books
authors has 3 entries for a book with 3 authors just using the book id and
the author is's
Olaf
On 2/9/09 10:25 AM, "PJ"
Just about the authors
You need a separate table for them and then an table linking authors and
books.
So you have table books, authors and rel_books_authors where rel_books
authors has 3 entries for a book with a authors just using the book id and
the author is's
Olaf
On 2/9/09 10:25 AM, "PJ"
being a newbie to mysql, I'm a little confused about how to deal with
the following:
I am creating a database of books and have come down to this - table for
books (books) including fields for
id (primary key, auto-incr.)
title
author (could be 2 or more)
category (could be several - eg. youth, fic
15 matches
Mail list logo
