Added copy() method for properties sharing

Author: avbdr

MysqliDb.php

@@ -769,6 +769,8 @@ protected function _prepareQuery()
     public function __destruct()
     {
         if (!$this->isSubQuery)
+            return;
+        if ($this->_mysqli)
             $this->_mysqli->close();
     }
 
@@ -931,4 +933,14 @@ public static function subQuery()
         return new MysqliDb();
     }
 
+    /**
+     * Method returns a copy of a mysqlidb subquery object
+     *
+     * @param object new mysqlidb object
+     */
+    public function copy ()
+    {
+        return clone $this;
+    }
+
 } // END class

readme.md

@@ -220,6 +220,20 @@ $products = $db->get ("products p", null, "u.name, p.productName");
 print_r ($products);
 ```
 
+### Properties sharing
+Its is also possible to copy properties
+```php
+$db->where ("agentId", 10);
+
+$customers = $common->copy ();
+$res = $customers->get ("customers");
+// SELECT * FROM customers where agentId = 10
+
+$db->orWhere ("agentId", 20);
+$res = $db->get ("users");
+// SELECT * FROM users where agentId = 10 or agentId = 20
+```
+
 ### Subqueries
 Subquery in selects:
 ```php
@@ -246,7 +260,6 @@ $data = Array (
 $id = $db->insert ("products", $data);
 // Gives INSERT INTO PRODUCTS (productName, userId, lastUpdated) values ("test product", (SELECT name FROM users WHERE id = 6), NOW());
 ```
-
 ### Helper commands
 Reconnect in case mysql connection died
 ```php

tests.php

@@ -228,8 +228,9 @@ function createTable ($name, $data) {
 $usersQ->where ("login", "user2");
 $usersQ->getOne ("users", "id");
 
-$db->where ("userId", $usersQ);
-$res = $db->getOne ("products", "count(id) as cnt");
+$db2 = $db->copy();
+$db2->where ("userId", $usersQ);
+$res = $db2->getOne ("products", "count(id) as cnt");
 if ($res['cnt'] != 2) {
     echo "Invalid select result with subquery";
     exit;