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Posted to derby-user@db.apache.org by Teja <te...@synapse.ws> on 2007/08/09 22:31:07 UTC

check if DB exists already?

How do I check if the database exists already? I know create=true in the
connection url creates if db doesn't exist and throws a SQLWarning if exists
already, but is there a way to know for sure that a database exists already
before connecting?
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Re: check if DB exists already?

Posted by Teja <te...@synapse.ws>.
Bernt,Kathy

Thanks for your replies.. I will do as suggested.



Teja wrote:
> 
> If the database doesn't exist, I need to initalize it, create some tables
> and stuff... What should I do instead?
> 
> 
> Daniel John Debrunner-2 wrote:
>> 
>> Teja wrote:
>>> How do I check if the database exists already? I know create=true in the
>>> connection url creates if db doesn't exist and throws a SQLWarning if
>>> exists
>>> already, but is there a way to know for sure that a database exists
>>> already
>>> before connecting?
>> 
>> Why not just attempt a connection? What do you gain by knowing if the 
>> database exists or not?
>> 
>> Dan.
>> 
>> 
> 
> 

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Re: check if DB exists already?

Posted by Kathey Marsden <km...@sbcglobal.net>.
Teja wrote:
> If the database doesn't exist, I need to initalize it, create some tables and
> stuff... What should I do instead?
>   
You could try to connect without create=true, if you get an SQLState 
XJ004 no database is there.

ij> connect 'jdbc:derby:mydb';
ERROR XJ004: Database 'mydb' not found.
ij>

Kathey



Re: check if DB exists already?

Posted by Teja <te...@synapse.ws>.
Brenty, Kathy
Thanks a lot for your time. I will do as suggested.

Teja wrote:
> 
> If the database doesn't exist, I need to initalize it, create some tables
> and stuff... What should I do instead?
> 
> 
> Daniel John Debrunner-2 wrote:
>> 
>> Teja wrote:
>>> How do I check if the database exists already? I know create=true in the
>>> connection url creates if db doesn't exist and throws a SQLWarning if
>>> exists
>>> already, but is there a way to know for sure that a database exists
>>> already
>>> before connecting?
>> 
>> Why not just attempt a connection? What do you gain by knowing if the 
>> database exists or not?
>> 
>> Dan.
>> 
>> 
> 
> 

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Re: check if DB exists already?

Posted by "Bernt M. Johnsen" <Be...@Sun.COM>.
>>>>>>>>>>>> Teja wrote (2007-08-09 14:09:27):
> 
> If the database doesn't exist, I need to initalize it, create some tables and
> stuff... What should I do instead?

try {
   c = DriverManager.getConnection('...url...');
} catch (SQLException.....) {
   c = DriverManager.getConnection('...url...;create=true');
   .... initialize it, create tables and stuff
}

Just fill in the details. This should be fairly straight forward.


> 
> 
> Daniel John Debrunner-2 wrote:
> > 
> > Teja wrote:
> >> How do I check if the database exists already? I know create=true in the
> >> connection url creates if db doesn't exist and throws a SQLWarning if
> >> exists
> >> already, but is there a way to know for sure that a database exists
> >> already
> >> before connecting?
> > 
> > Why not just attempt a connection? What do you gain by knowing if the 
> > database exists or not?
> > 
> > Dan.
> > 
> > 
> 
> -- 
> View this message in context: http://www.nabble.com/check-if-DB-exists-already--tf4245044.html#a12080833
> Sent from the Apache Derby Users mailing list archive at Nabble.com.
> 

Re: check if DB exists already?

Posted by Teja <te...@synapse.ws>.
If the database doesn't exist, I need to initalize it, create some tables and
stuff... What should I do instead?


Daniel John Debrunner-2 wrote:
> 
> Teja wrote:
>> How do I check if the database exists already? I know create=true in the
>> connection url creates if db doesn't exist and throws a SQLWarning if
>> exists
>> already, but is there a way to know for sure that a database exists
>> already
>> before connecting?
> 
> Why not just attempt a connection? What do you gain by knowing if the 
> database exists or not?
> 
> Dan.
> 
> 

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Re: check if DB exists already?

Posted by Daniel John Debrunner <dj...@apache.org>.
Teja wrote:
> How do I check if the database exists already? I know create=true in the
> connection url creates if db doesn't exist and throws a SQLWarning if exists
> already, but is there a way to know for sure that a database exists already
> before connecting?

Why not just attempt a connection? What do you gain by knowing if the 
database exists or not?

Dan.

Re: check if DB exists already?

Posted by Teja <te...@synapse.ws>.
I have to say that really sucks.. They could've easily comeup with a system
function that would check if a db exists or not instead of the user doing
directory and file checks. But then, it is free, so I cann't complain much..


dmclean62 wrote:
> 
> A Derby database is a directory containing a fairly distinctive set of
> files. You could use file system operations to see if a directory by that
> name exists and then check to see if it has the right files.
> 
> Donald
> 
>  -------------- Original message ----------------------
> From: Teja <te...@synapse.ws>
>> 
>> How do I check if the database exists already? I know create=true in the
>> connection url creates if db doesn't exist and throws a SQLWarning if
>> exists
>> already, but is there a way to know for sure that a database exists
>> already
>> before connecting?
>> -- 
>> View this message in context: 
>> http://www.nabble.com/check-if-DB-exists-already--tf4245044.html#a12080193
>> Sent from the Apache Derby Users mailing list archive at Nabble.com.
>> 
> 
> 
> 

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