Yes, that is Jira entry DERBY-2678 (Derby should follow SQL standards when operand(s) in the collation operation have collation derivation of NONE). I agree that we should mention that in the method comments and I will also update DERBY-2678 that changes will be needed in the method when we work on DERBY-2678.
Mamta On 7/31/07, Daniel John Debrunner <[EMAIL PROTECTED]> wrote: > > [EMAIL PROTECTED] wrote: > > Author: mamta > > Date: Tue Jul 31 13:48:39 2007 > > New Revision: 561514 > > > > URL: http://svn.apache.org/viewvc?view=rev&rev=561514 > > Log: > > Adding comment to the function that was added for DERBY-2793 > > > > > > Modified: > > > db/derby/code/trunk/java/engine/org/apache/derby/iapi/types/DataTypeDescriptor.java > > > > Modified: > db/derby/code/trunk/java/engine/org/apache/derby/iapi/types/DataTypeDescriptor.java > > URL: > http://svn.apache.org/viewvc/db/derby/code/trunk/java/engine/org/apache/derby/iapi/types/DataTypeDescriptor.java?view=diff&rev=561514&r1=561513&r2=561514 > > > ============================================================================== > > --- > db/derby/code/trunk/java/engine/org/apache/derby/iapi/types/DataTypeDescriptor.java > (original) > > +++ > db/derby/code/trunk/java/engine/org/apache/derby/iapi/types/DataTypeDescriptor.java > Tue Jul 31 13:48:39 2007 > > @@ -1155,6 +1155,25 @@ > > return false; > > } > > > > + /** > > + * Compare the collation info on this DTD with the passed DTD. The > rules > > + * are as follows > > + * 1)If both the DTDs have collation derivation of NONE, then they > can't be > > + * compared and we return false. > > + * 2)If both the DTDs have same collation derivation (which in > Derby's case > > + * at this point will mean collation derivation of IMPLICIT), then > check > > + * the collation types. If they match, then return true. If they > do not > > + * match, then they can't be compared and hence return false. > > + * > > + * In future, when we do support collation derivation of EXPLICIT, > we will > > + * need to change this method so that we follow the correct SQL > standard > > + * rules about what should happen if one collation derivation is > EXPLICIT > > + * and other is NONE/IMPLICIT. > > Isn't it true that even without supporting EXPLICT that algorithm in the > method is a subset of the SQL standard? IMPLICIT,NONE should succeed, > but will fail with this algorithm. > > Dan. > >
