Foreign key

[Bruno Guerpillon]

Hi

First, i assume i RTFM but am new to MySQL world so i got some problems.
I got 2 tables

TABLE1
T1Col1 Varchar(30) PRIMARY KEY

TABLE2
T2col1
T2col2



What i'd like to do is to set the T2col2 as foreign key for the T1Col1.
Any1 got the synthaxe to do it ?

Regards
Bruno

[Giuseppe Maxia]

Bruno Guerpillon wrote:

> Hi
>
> First, i assume i RTFM but am new to MySQL world so i got some problems.
> I got 2 tables
>
> TABLE1
> T1Col1 Varchar(30) PRIMARY KEY
>
> TABLE2
> T2col1
> T2col2
>
>
>
> What i'd like to do is to set the T2col2 as foreign key for the T1Col1.
> Any1 got the synthaxe to do it ?
>
> Regards
> Bruno
>
>

To use foreign keys, you have to:
- use InnoDB tables;
- have a primary key in the parent table
- have a key for the foreign key candidate column in the child table
- use the constraint syntax:
CONSTRAINT `constraint_name` FOREIGN KEY `key_name` (T2col2) references TABLE1 (T1Col1)

This is the RTFM part :)
[url]http://dev.mysql.com/doc/refman/5.0/en/innodb-foreign-key-constraints.html[/url]
[url]http://dev.mysql.com/doc/refman/5.0/en/example-foreign-keys.html[/url]
[url]http://dev.mysql.com/doc/refman/5.0/en/ansi-diff-foreign-keys.html[/url]

ciao
gmax

--
_ _ _ _
(_|| | |(_|>< The Data Charmer
_|
[url]http://datacharmer.blogspot.com/[/url]

[Jim Michaels]

If you've installed MySQL locally, it comes with a pretty decent manual,
especially if it's on Windows. you just go into the index tab and type in
alter table. you can also learn about alter table by looking at the SQL
generated when you modify a table in the query browser.
I think the syntax would look something like
ALTER TABLE TABLE2 ADD FOREIGN KEY ix_t2t2col2t1col1 (T2col2) REFERENCES
TABLE1(T1Col1);

"Bruno Guerpillon" <toto@toto.fr> wrote in message
news:43d60d41$0$375$636a55ce@news.free.fr...

> Hi
>
> First, i assume i RTFM but am new to MySQL world so i got some problems.
> I got 2 tables
>
> TABLE1
> T1Col1 Varchar(30) PRIMARY KEY
>
> TABLE2
> T2col1
> T2col2
>
>
>
> What i'd like to do is to set the T2col2 as foreign key for the T1Col1.
> Any1 got the synthaxe to do it ?
>
> Regards
> Bruno
>