data query specification

In most cases of communication among applications, 
a method of data query is very important. This topic
is not only in a communication protocol of applications.
We should concern it in the current discussions for 
message contents of the XML.

$B#X#M#L$N%a%C%;!o!"#R#D#B$NLd$$9g$o$;$G$O!"#S#Q#L$rMQ$$$^$9$,!"$^$:(B
$B$3$NCf$N#S#E#L#E#C#TJ8$K$D$$$F9M$(J}$k$H!"(B

SELECT A FROM B WHERE C

$B$H$J$j!"#A$,%U%#!!"#B$,%F!!"#C$,>r7o!"#C$,4pK\MWAG$N>r7or7o$NCf$+$i(B
$B0lCW$9$k%G!$NJ8;z$G$"$k>l9g$K$O!"%-!@\A*Br$5$l$^$9!#(B

In this query representation, you can describe several 
elements at one time. The conditions of those elements
are interpreted conjunctively.

$B$3$N>l9g!"(B<item>$B%?%0$O!"J#?t@_Dj$9$k$3$H$,2DG=$G$"$j!"(B
$BJ#?t$N%?%0$K$h$C$F;XDj$5$l$?>r7o$O#O#R$H$7$FF/$-$^$9!#$D$^$j(B
$B3FA*Br>r7o$GA*Br$5$l$?FbMF$NOB=89g$,7k2L$H$7$FJV$5$l$^$9!#(B

The value A in the SQL does not correspond to any data
in the XML representation. The response information would
depend on the message contexts, so that I think that
this information should be in the application protocol level.

$B$=$l$G!"#S#E#L#E#C#TJ8$N#A$KAjEv$9$k$I$N$h$&$JFbMF$rJV$9$+(B
$B$G$9$,!"#P#S#L#X$K$O$=$N$h$&$J@_Dj5-=R$,$"$k$N$G$9$,!"$I$&$b(B
$B;H$$>!<j$,$o$k$=$&$J$N$G!"#O#A#S#I#S$G$O:o=|$7$?$$$H;W$C$F(B
$B$$$^$9!#$3$l$O!"%a%C%;!<%8%3%s%F%-%9%H!JAw?.%a%C%;!<%8$4$H$K(B
$B@_Dj$9$k%Q%i%a!<%?!K$NB&$K$b$?$;$F!"%3%s%F%s%DB&$K$O;}$?$;$J$$(B
$B$[$&$,$$$$$H;W$C$F$$$^$9!#(B

-- 
Yasu Nissy (Yasuyuki NISHIOKA), Dr.Eng.
MIT, 41-211
77 Massachusetts Ave
Cambridge MA 02139
Phone 617-452-2982, Fax 617-253-2249
 <>