> -----Original Message----- > From: Thomas Sundberg > Sent: Friday, February 04, 2005 07:48 > To: mysql@lists.mysql.com > > > > -----Original Message----- > > From: Michael Stassen > > Sent: den 4 februari 2005 14:19 > > To: Thomas Sundberg > > Cc: mysql@lists.mysql.com > > > > From the manual, "where_definition consists of the keyword > > WHERE followed by an expression that indicates the condition > > or conditions that rows must satisfy to be selected." > > <http://dev.mysql.com/doc/mysql/en/select.html> > > > > That seems simple and straightforward to me. Perhaps if you > > told us why you need this, someone could provide you with the > > answer you need. > > It is very simple but absolutely not straight forward. It > really doesn't say > anything. Just that you should do things right and then you > will not have > any problems. > The concrete problem I tried to solve were if MySQL supports > xor in a where > clause. And if so, how should the syntax be written? That
Yes, you can use XOR in the where clause. SELECT * FROM mytable WHERE col1 XOR col2; This is not a bitwise XOR, it evaluates each column to true or false first then evals the XOR. example for an int column: a | b | eval ------------ 0 | 0 | false 1 | 0 | true 1 | 1 | false -1| 12| false 12| 0 | true > would have been > extremely simple if the syntax diagram started just above the > quote you > supplied us with had been completed and not ended when things > got a bit > interesting. > > /Thomas --- Tom Crimmins Interface Specialist Pottawattamie County, Iowa -- MySQL General Mailing List For list archives: http://lists.mysql.com/mysql To unsubscribe: http://lists.mysql.com/[EMAIL PROTECTED]
