New Post: SPUpdateMultipleListItems dynamic query and value?

I usually alert the query and value parameters to make sure they construct properly.

In my constructions, I don't have the backward slashes.  Also, the text strings are included in one double quote.  Try:

var query = "<Query><Where><Eq><FieldRef Name='bscParentTask' LookupId='TRUE'/><Value Type ='Lookup'>"+ taskID +"</Value></Eq></Where></Query>";
var value = "[['Date Completed', " + dateComp + "]]"