<?PHP
////////////////////////////////////////////////////////////////////
class MySQLResultSet implements Iterator{
//data members
private $strSQL;
private $databasename;
private $connection;
private $result;
private $valid;
private $currentrow;
private $key;
//programmer defined error numbers
//in range not used by MySQL
const INDETERMINATE_TOTAL_NUMBER = 5001;
const UNNECESSARY_SQL_CALC_FOUND_ROWS = 5002;
const NOT_SELECT_QUERY = 5003;
////////////////////////////////////////////////////////////////////
//constructor
////////////////////////////////////////////////////////////////////
public function __construct( $strSQL, $databasename, $connection ){
$this->strSQL = $strSQL;
$this->connection = $connection;
$this->databasename = $databasename;
}
if(!$this->result = mysql_query($strSQL, $connection)){ }
//check if contains SQL_CALC_FOUND_ROWS
if (stristr($strSQL,"SQL_CALC_FOUND_ROWS")){ $msg = "No need to use SQL_CALC_FOUND_ROWS.";
throw new MySQLException($msg, self::UNNECESSARY_SQL_CALC_FOUND_ROWS);
}
//initialize values (not necessary for foreach)
$this->rewind();
}
////////////////////////////////////////////////////////////////////
//destructor
////////////////////////////////////////////////////////////////////
public function __destruct(){
$this->close();
}
////////////////////////////////////////////////////////////////////
// public methods
////////////////////////////////////////////////////////////////////
public function getDatabaseName(){
return $this->databasename;
}
////////////////////////////////////////////////////////////////////
public function getNumberColumns(){
}
////////////////////////////////////////////////////////////////////
//For select queries only
////////////////////////////////////////////////////////////////////
public function getNumberRows(){
}
////////////////////////////////////////////////////////////////////
public function getInsertId(){
}
////////////////////////////////////////////////////////////////////
//Calculate total number of records if a limit clause present
//Useful for calculating number of pages in versions < 4
//Unreliable results if DISTINCT used
////////////////////////////////////////////////////////////////////
public function getUnlimitedNumberRows(){
$number = 0;
$versionnumber = $this->findVersionNumber();
//only need leftmost number
$version = substr($versionnumber,0
,1
); //CHECK SELECT
if (!$this->checkForSelect()){
$msg = "Illegal method call - not a SELECT query";
throw new MySQLException($msg, self::NOT_SELECT_QUERY);
}
//check for limit clause
$end = strpos($tempsql,"LIMIT"); if ($end === false){ //no limit clause
}
elseif($version < 4){
$number = $this->countVersionThree($end);
}else{ //version 4 or higher use SQL_CALC_FOUND_ROWS function
$number = $this->countVersionFour();
}
return $number;
}
////////////////////////////////////////////////////////////////////
public function getFieldNames(){
if(isset($this->result)){ for($i = 0; $i < $num; $i++){
}else{
$fieldnames[$i]= $meta->name;
}
}
}
return $fieldnames;
}
////////////////////////////////////////////////////////////////////
public function findVersionNumber(){
//mysql_get_server_info
}
////////////////////////////////////////////////////////////////////
//Iterator methods that must be implemented
////////////////////////////////////////////////////////////////////
return $this->currentrow;
}
////////////////////////////////////////////////////////////////////
return $this->key;
}
////////////////////////////////////////////////////////////////////
$this->valid = true;
$this->key++;
}else{
$this->valid = false;
}
}
////////////////////////////////////////////////////////////////////
$this->valid = true;
$this->key = 0;
}
}else{
$this->valid = false;
}
}
////////////////////////////////////////////////////////////////////
public function valid (){
return $this->valid;
}
////////////////////////////////////////////////////////////////////
//private methods
////////////////////////////////////////////////////////////////////
private function checkForSelect(){
$bln = true;
if(substr($strtemp,0,6)!= "SELECT"){ $bln = false;
}
return $bln;
}
////////////////////////////////////////////////////////////////////
private function close(){
if(isset($this->result)){ }
}
////////////////////////////////////////////////////////////////////
private function countVersionFour(){
$tempsql = trim($this->strSQL); //insert SQL_CALC_FOUND_ROWS
$insertstr = " SQL_CALC_FOUND_ROWS ";
//already know it starts with "SELECT"
}
$tempsql = "SELECT FOUND_ROWS()";
}
$number = $row[0];
//dispose of $rs
return $number;
}
////////////////////////////////////////////////////////////////////
private function countVersionThree($end){
//check for DISTINCT - will throw things off
if(!strpos($tempsql,"DISTINCT")){ //create recordset
$start = strpos($tempsql,"FROM"); $numchars = $end-$start;
$countsql = "SELECT COUNT(*) ";
$countsql .= substr($this->strSQL, $start, $numchars); }
$number = $row[0];
//dispose of $rs
}else{
$msg = "Using keyword DISTINCT, ".
"calculate total number manually.";
//must use self - not a property
throw new MySQLException($msg, self::INDETERMINATE_TOTAL_NUMBER);
}
return $number;
}
}//end class
?>
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ясно понятно, всем спасибо 
еще понел полиморфизм но это уже не по теме 
