When you want to determine the order of articles into an sequence returned by an XQuery query, you can use the << and >> operators:
- X << Y: is true if X is before Y;
- X >> Y: is true if Y is before X;
For example, suppose you have the following sequence of strings:
Shark, Daisy, Hunter, Lego, Helly
Use this query:
let $xml:=doc(?file:///C://Data_Local//xml//AirWings.xml?)
for $a in $xml/company/aircrafts
for $b in $xml/company/aircrafts
return(if($a/type<<$b/type) then concat($a/type/@M,"--]",$b/type/@M)
else concat($a/type/@M,"[--",$b/type/@M)
)
The query returns:
Shark[--Shark, Shark--]Daisy, Shark--]Hunter, Shark--]Lego,
Shark--]Helly, Daisy[--Shark, Daisy[--Daisy, Daisy--]Hunter,
Daisy--]Lego, Daisy--]Helly, Hunter[--Shark, Hunter[--Daisy,
Hunter[--Hunter, Hunter--]Lego, Hunter--]Helly, Lego[--Shark,
Lego[--Daisy, Lego[--Hunter, Lego[--Lego, Lego--]Helly ,
Helly[--Shark, Helly[--Daisy, Helly[--Hunter, Helly[--Lego,
Helly[--Helly