[
https://issues.apache.org/jira/browse/DERBY-5525?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=13165330#comment-13165330
]
Knut Anders Hatlen commented on DERBY-5525:
-------------------------------------------
Moving the constant folding earlier, so that it happens before the bind phase,
seems to do the trick:
ij> values upper('Straße');
1
-------
STRASSE
1 row selected
Currently, constant folding happens in the beginning of the optimize phase. I
vaguely recall there was a reason to put it exactly there, but I don't remember
now.
Even if constant folding would solve the case with a string literal argument,
there's still the general problem with "select ucase(a) from ...", mentioned by
Rick. Unless we have some knowledge about the locale that we could use to come
up with a better estimate, I think we'll have to set the precision to the
maximum varchar length. (I also wonder what happens if we have a string close
to the maximum length, and converting it to upper case makes it longer than the
maximum length. Might run into problems similar to DERBY-4793.)
> Precision for UPPER function is wrong if the returned value is longer than
> the literal argument
> -----------------------------------------------------------------------------------------------
>
> Key: DERBY-5525
> URL: https://issues.apache.org/jira/browse/DERBY-5525
> Project: Derby
> Issue Type: Bug
> Components: SQL
> Affects Versions: 10.8.2.2
> Reporter: Knut Anders Hatlen
>
> Seen in ij in a database with territory based collation and German locale:
> ==vv= COPIED FROM IJ CONSOLE =vv==
> ij> VALUES UCASE('Straßenbahn');
> 1
> -----------
> STRASSENBA&
> 1 Zeile ausgewählt
> ==================================
> And with JDBC calls:
> Connection c = DriverManager.getConnection(
> "jdbc:derby:memory:db;create=true;territory=de_DE;" +
> "collation=TERRITORY_BASED");
> Statement s = c.createStatement();
> ResultSet rs = s.executeQuery("values upper('Straße')");
> System.out.println(rs.getMetaData().getPrecision(1));
> rs.next();
> System.out.println(rs.getString(1));
> This prints
> 6
> STRASSE
> The precision is wrong, since the returned value is 7 characters long.
--
This message is automatically generated by JIRA.
If you think it was sent incorrectly, please contact your JIRA administrators:
https://issues.apache.org/jira/secure/ContactAdministrators!default.jspa
For more information on JIRA, see: http://www.atlassian.com/software/jira
