Galax is installed in the following two directories:
/cse/courses/csep544/Galax/Galax-0.5.0-MinGW/bin --- the Windows version
/cse/courses/csep544/Galax/Galax-0.5.0-Linux/bin --- the Linux version
Technically, that's all you need to know to do the homework problems on
XQuery. For a more gentle introduction on how to use Galax, read on.
This small tutorial is for Linux only. For Windows, go back in the browser
and click on the other link.
1. Type:
cd /cse/courses/csep544/Galax
2. Type 'ls -al'.
mondial-3.0.xml is a copy of the XML document you will use for the homework.
3. Look at the files q1.xq and q2.xq. For q1.xq you should see:
{ for $x in document("mondial-3.0.xml")/mondial/country//city/name/text()
return
{ $x }
}
For q2.xq you should see:
{ for $x in document("mondial-3.0.xml")/mondial/country[@name="Peru"]/province[count(city)>1]/@name
return
{ fn:string($x) }
}
!!! Note: Using "fn:string" is because $x is an attribute. This is one way to return the value of an attribute.
4. Type:
Galax-0.5.0-Linux/bin/galax-run q1.xq
In a few seconds galax will print the result for you. In this case
it's the list of all city names in the database. Notice that
cities occur either under country, or under province. In order to
get both we used country//city.
5. Now try
Galax-0.5.0-Linux/bin/galax-run q2.xq
You are getting the names of all provinces in Peru with at least
two cities.
6. Finally, try:
Galax-0.5.0-Linux/bin/galax-run q2.xq > ~/myfile.xml
This creates myfile.xml in HOME directory with your result.