db-derby-dev mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From "Eranda Sooriyabandara (JIRA)" <j...@apache.org>
Subject [jira] Updated: (DERBY-3173) Removed cached String objects from SQLDate, SQLTime and SQLTimestamp
Date Thu, 26 Aug 2010 17:11:54 GMT

     [ https://issues.apache.org/jira/browse/DERBY-3173?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel
]

Eranda Sooriyabandara updated DERBY-3173:
-----------------------------------------

    Attachment: Derby-3173.diff

Hi Knut,
Thanks for got the thing and I did the changes as you suggest and here I am attaching the
patch with this. It seems to be working now.

ij> values time('05 am pm'); 
ERROR 22007: The syntax of the string representation of a datetime value is incorrect.
ij> values time('05 am');            
1       
--------
05:00:00

1 row selected
ij> values time('05 pm');    
1       
--------
17:00:00

1 row selected

thanks

> Removed cached String objects from SQLDate, SQLTime and SQLTimestamp
> --------------------------------------------------------------------
>
>                 Key: DERBY-3173
>                 URL: https://issues.apache.org/jira/browse/DERBY-3173
>             Project: Derby
>          Issue Type: Improvement
>          Components: SQL
>            Reporter: Daniel John Debrunner
>            Assignee: Eranda Sooriyabandara
>            Priority: Minor
>         Attachments: Derby-3173.diff, Derby-3173.diff, Derby-3173.diff, sqldate.diff
>
>
> These type classes save a copy of the value when it is converted to a String (e.g. through
a ResultSet.getString()). This complicates the code & increases memory use for little
value, in most cases the cached value will never be used. E.g. for any type of scan the String
value will be discarded when moving to the next row. In most cases applications do not call
getString() twice on a column.
> The code has some historical basis in the fact that these types used to be represented
by a java.sql.Time/Date/Timestamp object and its conversion to String was slow. Now the conversion
of all these types to a String is simple.
> In addition I think the getString() will sometimes return a non-normalized form, if the
value is set by a non-standard format then the cached String is set to the non-standard format,
not the standard format, I believe this is incorrect.

-- 
This message is automatically generated by JIRA.
-
You can reply to this email to add a comment to the issue online.


Mime
View raw message