The correct thing to do is actually implement GROUP_CONCAT. Just check the code base and find all the uses of Token.T_SUM and Expression.SUM. Then add a new Token.T_GROUP_CONCAT and a new Expression.GROUP_CONCAT and some code to handle this case to all the places where Token.T_SUM and Expression.SUM are used. It's actually quite simple.
Fred ----- Original Message ----- From: "Werner, Wolfgang" <[EMAIL PROTECTED]> To: <[email protected]> Sent: 09 September 2005 01:35 Subject: Re: [Hsqldb-developers] SUM for Strings -----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1 Hi again, I just noticed that my change breaks some of the unit tests. I'll have another look at it. Sorry for bothering, Wolfgang Werner, Wolfgang wrote: > Hi, > > I needed something similar to MySQLs GROUP_CONCAT and came up with the > following hack: > I simply added a concat operation for VARCHAR to the SUM function. This > is my first contact with hsqldb, so if this patch is a bad idea please > clarify. > I guess it would be more consistent to add a completely new aggregate > function, but does it do any harm this way? > > I didn't want to post it on the patch tracker since I'm new to the list > and don't know if this is appropriate, so it is attached. > > Btw. hsqldb is really great work. Using it the first time today and > already loving it. Thanks! > > Regards, > Wolfgang > > <diff args='-cb'> > *** SetFunction.java Fri Jul 8 16:13:00 2005 > --- SetFunction.java.ww Fri Sep 9 02:22:26 2005 > *************** > *** 137,142 **** > --- 137,150 ---- > currentBigDecimal.add((BigDecimal) > item); > } > > + case Types.VARCHAR: > + if (currentValue == null) { > + currentValue = (String) item; > + } else { > + currentValue = > + currentValue.toString().concat((String)item); > + } > + > return; > > default : > *************** > *** 266,271 **** > --- 274,282 ---- > case Types.DECIMAL : > return currentBigDecimal; > > + case Types.VARCHAR: > + return (String)currentValue; > + > default : > throw Trace.error(Trace.SUM_OF_NON_NUMERIC); > } > </diff> - ------------------------------------------------------- SF.Net email is Sponsored by the Better Software Conference & EXPO September 19-22, 2005 * San Francisco, CA * Development Lifecycle Practices Agile & Plan-Driven Development * Managing Projects & Teams * Testing & QA Security * Process Improvement & Measurement * http://www.sqe.com/bsce5sf _______________________________________________ hsqldb-developers mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/hsqldb-developers -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.0 (Cygwin) Comment: Using GnuPG with Thunderbird - http://enigmail.mozdev.org iD8DBQFDINjIqjaicDyx8o8RAhEUAJ9toyddM/sm3aEM+YAII53AAPZQ7ACfRQKT 4cMEljf00z2IWKUV+w1AlWE= =LyNQ -----END PGP SIGNATURE----- ------------------------------------------------------- SF.Net email is Sponsored by the Better Software Conference & EXPO September 19-22, 2005 * San Francisco, CA * Development Lifecycle Practices Agile & Plan-Driven Development * Managing Projects & Teams * Testing & QA Security * Process Improvement & Measurement * http://www.sqe.com/bsce5sf _______________________________________________ hsqldb-developers mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/hsqldb-developers ------------------------------------------------------- SF.Net email is Sponsored by the Better Software Conference & EXPO September 19-22, 2005 * San Francisco, CA * Development Lifecycle Practices Agile & Plan-Driven Development * Managing Projects & Teams * Testing & QA Security * Process Improvement & Measurement * http://www.sqe.com/bsce5sf _______________________________________________ hsqldb-developers mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/hsqldb-developers
