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Re: InstantDB: Zero-length strings



So is this a verified bug?  InstantDB is free (thanks, btw), and I'm just 
using it for a pet project, so I can live without a fix, no problem.  I 
just wanted to make sure that I wasn't doing something wrong (wildcard 
syntax seems to vary a bit amongst SQL implementations, and I'm not exactly 
a DB guru).

While I'm on the topic of bugs/enhancements, I found InstantDB doesn't 
appear to support inserting rows programmatically, and then reading the 
changed row, as described by Sun for JDBC 2.0 
http://developer.java.sun.com/developer/Books/JDBCTutorial/ 
under sections 3.3.3 and 3.3.4.  I'm not sure what version of JDBC 
InstantDB is intended to support, and I actually think that the ability 
to read back programmatic updates to a resultset is left as 
implementation-specific ("In a ResultSet object that is 
TYPE_SCROLL_INSENSITIVE, you cannot see changes made to it by others while 
it is still open, but you may be able to see your own changes with some 
implementations.")  Just FYI.  In any case, I don't expect the most 
advanced and obscure functionality in InstantDB and wouldn't trade it for 
compactness or performance anyway...it does just fine for what it was 
designed ;)

Thanks,
Aaron Hamid

> I don't think you're doing anything wrong. % should match zero or more 
> characters, so I think it ought to match an empty string. I can't promise
> when you'll see a fix for this though. Is it likely to cause you major
> problems?
>
> Pete
> ----- Original Message -----
> From: <arh14@cornell.edu>
> To: <instantdb@enhydra.org>
> Sent: Wednesday, February 21, 2001 8:36 PM
> Subject: InstantDB: Zero-length strings
>
>
>> It seems that zero-length strings in an insert statement result in nulls
>> in the database.  Either that or the % wildcard is not working.  My
>> problem is that when I insert some non-null zero-length string values
>> into some columns
>>
>> e.g. INSERT INTO Foo VALUES ('','','')
>>
>> an immediate search with wildcards fails
>>
>> e.g. SELECT * FROM FOO WHERE Col1 LIKE '%%' AND Col2 LIKE '%%' AND 
>Col3 LIKE '%%'
>>
>> To my understanding % should collaps to "any non-null string value", so
>> %% should be matching the zero-length string values.  The second I 
>> change the insert statement to insert strings consisting of a single
>> space  character, the select statement works.
>>
>> Am I doing something wrong here?
>>
>> Aaron Hamid
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