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Date: Mon, 17 Dec 2007 10:42:28 +0100
From: Dyre.Tjeldvoll@Sun.COM
Subject: Re: newbie question
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Brad Berens <theg33k@gmail.com> writes:

> I've googled for this but all I can find is create statements so I'm hoping
> someone can just give me a quick answer.  I'm trying to write some db
> creation scripts.  Normally in MSSQL I would use an if exists from the
> system tables to check whether or not to run a drop before creating the
> table.  I found the sys.systables info about derby, but I can't seem to get
> the if clause working for that.
>
>
> IF EXISTS (SELECT * FROM sys.systables WHERE tablename='[tablename]') DROP
> TABLE [tablename];

IF EXISTS is a non-std extension AFAICT. You can do this portably by
using DatabaseMetaData.getTables(...). It is a bit more work so you might
want to wrap it in a java method.

-- 
dt