GH #32: Fix evaluation of bound join using VALUES clause

It turned out that query engines interprete the scope of the VALUES
differently when it is in the WHERE block or outside.

This change fixes the issue by putting the VALUES clause inside the
WHERE block, which seems to work on all tested engines.

Author: Andreas Schwarte

Diff for: src/com/fluidops/fedx/util/QueryStringUtil.java

@@ -310,8 +310,9 @@ public static String selectQueryStringBoundUnion( StatementPattern stmt, List<Bi
 	 * 
 	 * <source>
 	 * SELECT ?v ?__index WHERE {
+	 *   VALUES (?s ?__index) { (:s1 1) (:s2 2) ... (:sN N) }
 	 *   ?s name ?v.
-	 * } VALUES (?s ?__index) { (:s1 1) (:s2 2) ... (:sN N) }
+	 * } 
 	 * </source>
 	 * 
 	 * @param stmt
@@ -339,14 +340,12 @@ public static String selectQueryStringBoundJoinVALUES(StatementPattern stmt, Lis
 
 		res.append(" ?").append(BoundJoinVALUESConversionIteration.INDEX_BINDING_NAME).append(" WHERE {");
 
-		res.append( stmtPattern );
 
 		// TODO evaluate filter expression remote
 //		if (filterExpr!=null) {
 //		
 //		}
 
-		res.append(" }");
 
 		// add VALUES clause
 		res.append(" VALUES (");
@@ -368,6 +367,11 @@ public static String selectQueryStringBoundJoinVALUES(StatementPattern stmt, Lis
 			res.append("\"").append(index).append("\") ");
 			index++;
 		}
+
+		res.append(" } ");
+
+		res.append(stmtPattern);
+
 		res.append(" }");
 
 		return res.toString();