[xsl] xsl:key() and $variables.

[Steve <subsume@xxxxxxxxx>]

I have a variable containing

<Records>
  <Record>
     <activity>Baseball</
     <hours>36</
  <Record>
     <activity>Shopping</
     <hours>39</
  <Record>
     <activity>Writing</
     <hours>3</
   ......etc  (yes, I know they're not closed.)

and some xml (document('../blah.xml') containing...

<activities>
   <activity neccesary="no">Baseball</
   <activity neccesary="no">Shopping</
   <activity neccesary="yes">Writing</

..............

How do I  <xsl:apply-templates select="$variable/Records/Record[1]" />
only those records which are neccesary="yes"  ?

I swear one of these posts I'll have xsl:key figured out.

-Steve