Re: join syntax

On Tue, 17 Jun 2003, Jodi Kanter wrote:

> One of my colleagues has created a database where he has the same field
> name in two tables and uses this field to link his tables rather than
> some arbitrary value. For example, he has used "exp_id" in two tables.
> When writing his joins he uses a syntax that says something like JOIN ON
> EXP_ID. Can someone tell me what that syntax should be? I am not very
> familiar with it since I typically use the syntax where one field is set
> equal to the other.
> Personally I prefer not to set databases up this way but cannot seem to
> convince him of this. And yet I am supposed to now help him with his
> database and application.. Is there some documentation that would define
> this type of syntax? How is this handled if you have more than one table
> in the join? It does not appear that this format would allow for this.

If you're joining two tables on a field that has the same name you can use
a natural join.

select * from table1 natural join table2;