Derby features

[David Van Couvering <Da...@Sun.COM>]

Hi, all.  I am getting a bit of an RFP from an internal user and was
wondering if you could help answer Y/N/Partial on the following features
for Derby.  I have put in only those items I couldn't find with a fairly
close search through the ref manual.

- Character set configurable per connection
- Character set configurable per user
- Store data from different locales in same table and be able to sort
over them
- Array data type support (doesn't look like it)
- "Initially deferred" foreign key constraints (I don't even know what
this means)
- Coalesce/ifNull operator (I found NULLIF but I'm not sure that's the
same thing)
- Function-valued sorting
- limit, offset clauses in select for paging
- constraint violation error messages should contain constraint names

Thanks!

David

Re: Derby features

[Edson Carlos Ericksson Richter <ed...@mgrinformatica.com.br>]

Comments inline:

Daniel John Debrunner escreveu:

>David Van Couvering wrote:
>
>  
>
>>Hi, all.  I am getting a bit of an RFP from an internal user and was
>>wondering if you could help answer Y/N/Partial on the following features
>>for Derby.  I have put in only those items I couldn't find with a fairly
>>close search through the ref manual.
>>
>>- Character set configurable per connection
>>- Character set configurable per user
>>    
>>
>
>Not sure what this means in terms of Derby. Derby uses Java so there is
>the single character set, Unicode.
>
>  
>
>>- Store data from different locales in same table and be able to sort
>>over them
>>    
>>
>
>Derby supports Unicode as the only character set for all character data,
>so you can have a column with chinese text, english text and greek text,
>no restrictions.
>
>  
>
>>- Array data type support (doesn't look like it)
>>    
>>
>No.
>  
>
Could this be done storing an ArrayList object at database?

>  
>
>>- "Initially deferred" foreign key constraints (I don't even know what
>>this means)
>>    
>>
>I don't think so, but could be coded up.
>
>  
>
>>- Coalesce/ifNull operator (I found NULLIF but I'm not sure that's the
>>same thing)
>>    
>>
>
>COALESCE exists.
>  
>
Every function you can't find in Derby could be programmed in Java and 
added to database as DB Function or as DB Procedure. Is very easy to 
program them.

>  
>
>>- Function-valued sorting
>>    
>>
>
>Added in 10.1, ORDER BY expressions.
>
>  
>
>>- limit, offset clauses in select for paging
>>    
>>
>Is there a standard for this? Is a RowSet a better api?
>  
>
Since Derby uses server side controls, IMHO there is no need for this 
clauses. They will not reduce amount of work neither traffic on the 
network... But they easy development of applications a lot...

>  
>
>>- constraint violation error messages should contain constraint names
>>    
>>
>I thought they did, maybe in some cases they don't.
>  
>
AFAIK, yes... The constraint name appear in constraint violation errors. 
I've played a lot with Derby and found no exception until today.

>Dan.
>
>
>
>  
>
Richter

-- 
Edson Carlos Ericksson Richter
MGR Inform�tica Ltda.
Fones: 3347-0446 / 9259-2993

Re: Derby features

[Daniel John Debrunner <dj...@debrunners.com>]

David Van Couvering wrote:

> Hi, all.  I am getting a bit of an RFP from an internal user and was
> wondering if you could help answer Y/N/Partial on the following features
> for Derby.  I have put in only those items I couldn't find with a fairly
> close search through the ref manual.
> 
> - Character set configurable per connection
> - Character set configurable per user

Not sure what this means in terms of Derby. Derby uses Java so there is
the single character set, Unicode.

> - Store data from different locales in same table and be able to sort
> over them

Derby supports Unicode as the only character set for all character data,
so you can have a column with chinese text, english text and greek text,
no restrictions.

> - Array data type support (doesn't look like it)
No.

> - "Initially deferred" foreign key constraints (I don't even know what
> this means)
I don't think so, but could be coded up.

> - Coalesce/ifNull operator (I found NULLIF but I'm not sure that's the
> same thing)

COALESCE exists.

> - Function-valued sorting

Added in 10.1, ORDER BY expressions.

> - limit, offset clauses in select for paging
Is there a standard for this? Is a RowSet a better api?

> - constraint violation error messages should contain constraint names
I thought they did, maybe in some cases they don't.

Dan.