Update MP SELECT Descendants.md

Author: pchemguy

MP SELECT Descendants.md

@@ -113,11 +113,10 @@ SELECT * FROM records ORDER BY path;
 
 in which %SELECTOR% should be replaced according to the following table
 
-<pre>
-| node set    | %SELECTOR%                          |
-|-------------|-------------------------------------|
-| root nodes  | `cats.path    IN  (tops.path)`      |
-| descendants | `cats.prefix like tops.path || '%'` |
-| subtrees    | `cats.path   like tops.path || '%'` |
-| children    | `cats.prefix  =   tops.path`        |
-</pre>
+
+| node set    | %SELECTOR%                                      |
+|-------------|-------------------------------------------------|
+| root nodes  | <pre>cats.path    IN  (tops.path)</pre>         |
+| descendants | <pre>cats.prefix like  tops.path \|\| '%'</pre> |
+| subtrees    | <pre>cats.path   like  tops.path \|\| '%'</pre> |
+| children    | <pre>cats.prefix  =    tops.path</pre>          |