ORA-XQ-063-C: Please clarify what is a collation

SECTION 2.1.1: Static context

In-scope collations: it says that a collation "may be regarded
as an object that supports two functions...".  In F&O section 7.5
"Functions based on substring matching" fourth paragraph, it 
says "For other functions, such as fn:contains(), the collation
needs to support an additional property: it must be able to 
decompose the string into a sequence of collation units...".
This "additional property" appears to be the same as the second of the two functions in a collation object.  The choice of the words
"it must be able to..." in F&O suggests that F&O regards the
presence of this second function as optional.  Also, in F&O 7.5.1
"fn:contains", second para, last sentence, it says "If the 
specified collation is unsuitable ... an error may be raised."
What would make a collation unsuitable?  The reader is left
with the impression that one thing that might make a collation
unsuitable is if the collation does not support the second
function.  (Some other possibilities are mentioned in 
F&O 7.31 "Collations", including issues with normalization.)
Summary: please clarify 
whether the second function is a mandatory or an optional 
part of a collation object.  I am entering separate comments 
asking to clarify some of these points in F&O as well.

- Steve B.

Received on Monday, 16 February 2004 14:20:41 UTC