MySQL add, delete, modify, query tool PHP class

 In the past, the development project did not use a framework, and it was a very practical mysql tool class that was directly developed as object-oriented.

  header("content-type:text/html;charset=utf-8");
 class DBUtils{


 /**
 *General update method insert update delete operation
 *@param sql
 *@return bool true false
*/
 public function update($sql){
 $link = $this->getConn();
 mysql_query($sql);
 //If an error occurs
 if(DEBUG){
 echo mysql_error();
 }
 $rs = mysql_affected_rows($link);
 $rs = $rs > 0;
 mysql_close($link);
 return $rs;
 }

 /**
 *General query method select operation
 *@param sql
 *@return array
*/
 public function queryRows($sql){
 //Create connection, encoding , database
 $link = $this->getConn();
 //Send sql
 $rs = mysql_query($sql);
 //If an error occurs
 if(DEBUG){
 echo mysql_error();
 }


 $rows = array();
 while($row = mysql_fetch_array($rs)){
 $rows[] = $row;//pdemo7.php
 }
 //
 mysql_free_result($rs);
 mysql_close($link);
 return $rows;
 }


 /**
 *General query method select operation query result one row of data
 *@param sql
 *@return array Return false if failed;
*/
 public function queryRow($sql){
 $rs = $this->queryRows($sql);
 if (!empty($rs[0])){
 return $rs[0];
 }
 return false;
 }

 /**
 *General query method select operation Query result is one data
 *@param sql
 *@return array Return false if failed;
 * Example: select count(*) from user;
*/
 public function queryObj($sql){
 $rs = $this->queryRows($sql);
 //var_dump($rs);
 if(!empty($rs[0][0])){
 return $rs[0][0];
 }
 return false;
 }


 private function getConn(){
 $link = mysql_connect('127.0.0.1','root','');
 mysql_query("set names utf8");
 mysql_select_db(" news");
 return $link;
 }

 }

MySQL, PHP