fix dead link

Author: OStefan2001

public/md-articles/best-practice/insert-update-delete-statements-with-zend-db.md

@@ -94,4 +94,4 @@ A: Call $db->delete('user', 'id = '.$id), which is equivalent to the SQL stateme
 
 ## Resources
 
-- [Zend_Db series](http://www.dotkernel.com/dotkernel/sql-select-zend-db/)
+- [Zend_Db series](https://www.dotkernel.com/best-practice/sql-queries-using-zend-db-select/)

public/md-articles/best-practice/subqueries-with-zend-db.md

@@ -69,4 +69,4 @@ A: Use ->joinLeft(array('b'=>'track_courses'), 'a.id = b.track_id', array('count
 
 ## Resources
 
-- [Zend_Db series](http://www.dotkernel.com/dotkernel/sql-select-zend-db/)
+- [Zend_Db series](https://www.dotkernel.com/best-practice/sql-queries-using-zend-db-select/)