From: Martijn Tonies
Date: January 14 2004 11:35am
Subject: Re: Newbie - from Oracle
List-Archive: http://lists.mysql.com/mysql/157636
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Hi Ken,

> Oracle has "Dual" does MySql have something similar?

MySQL doesn't have a "dual" table. But if you take a look at the
"Dual" in Oracle, you'll only see this:

CREATE TABLE Dual (Dummy VARCHAR(1));
INSERT INTO Dual ('X');

So you can easily create one yourself.

> In Oracle I use SYSDATE and USER a lot as default column values when
> creating a table. Can you do something similar in MySql and how?

According to http://www.mysql.com/doc/en/CREATE_TABLE.html
a DEFAULT is:
"A DEFAULT value has to be a constant, it cannot be a function or an
expression."

> Does MySql support sequences? How?

No, not as seperate objects. It does support an auto-inc type column.

> Relationships - can the code be interfered with or do I have to wait for
> triggers?

Foreign key constraints? Only available in the "InnoDB" table type.
Read the docs on that.


With regards,

Martijn Tonies
Database Workbench - developer tool for InterBase, Firebird, MySQL & MS SQL
Server.
Upscene Productions
http://www.upscene.com