Memcache Use Example | Php

First of all, to determine whether there is a key in the memcache, if there is a value from the memcache, if there is no corresponding key, from the page to crawl data, if the capture is successful, then into the DB, write memcache and read, if the crawl is not successful, then directly in the MySQL value, and put the value taken out into memcache.

<?php include (' inc/common.inc.php ');

if (! isset ($city) | |! Is_array ($city)) {exit;}

Print_r ($city); exit;
$mem = new Memcache ();
$mem-> Connect (' localhost ', ' 11211 ');

$expires =15*60; Check if cache exits if (($value = $mem-> Get ($city))!= FALSE) {echo ' Get key from Memcache: '. '
	<br/> ";
	$return = $mem->get ($city);
echo Json_encode ($return);
	}//if else {$resultJson =fetch_data (); echo Count ($resultJson).
	<br/> "; if (count ($resultJson) ==1 | | empty ($resultJson)) {//from MySQL value echo "Get key from MySQL:". "
		<br/> ";
		$query = "SELECT * from PM25";
		$result =mysql_query ($query);
		while ($row = Mysql_fetch_assoc ($result)) {$rows []= $row;
			The array of acquired values is stored in memcache for ($i =0 $i <count ($rows), $i + +) {$k [$i]= $rows [$i] [' City '];
			$v [$i] [' City ']= $rows [$i] [' City '];
			$v [$i] [' PM25 ']= $rows [$i] [' PM25 '];
		$mem-> Set ($k [$i], $v [$i], False, $expires);
		}//$return = $mem->get ($city);
	echo Json_encode ($return);
}//if	else{echo "Get key from new_writed MySQL:".
		<br/> ";
		write_db ($resultJson);
		$query = "SELECT * from PM25";
		$result =mysql_query ($query);
		while ($row = Mysql_fetch_assoc ($result)) {$rows []= $row;
			//write memcache for ($i =0; $i <count ($rows); $i + +) {$k [$i]= $rows [$i] [' City '];
			$v [$i] [' City ']= $rows [$i] [' City '];
			$v [$i] [' PM25 ']= $rows [$i] [' PM25 '];
		$mem-> Set ($k [$i], $v [$i], False, $expires);
		}//$return = $mem->get ($city);
	echo Json_encode ($return);

}//else}//else foreach ($city as $k => $v) {$return [$k]= $mem->get ($v);} echo Json_encode ($return);
	function Fetch_data () {$url = "http://www.example.com";	
	$url = "";
	$data = Http_get ($url);
	$getJson = Json_decode ($data, true);
return $getJson;
	}//func fetch_data function write_db ($getJson) {$sql = "DELETE from PM25";
	mysql_query ($sql);
		Sort the Json.txt foreach ($getJson as $key => $row) {$area [$key] = $row [' area '];
	$PM 2_5[$key]= $row [' pm2_5 ']; } array_multisorT ($area, SORT_ASC, $pm 2_5,sort_asc, $getJson);
		For ($i =0 $i <count ($getJson)-1; $i + +) {if ($getJson [$i] [' pm2_5 ']==0] $count = 0;
		else $count = 1;
		$sum = $getJson [$i] [' pm2_5 ']; for ($j = $i +1; $j <count ($getJson); $j + +, $i + +) {if strcmp ($getJson [$j] [' area '], $getJson [$i]] ==0) {if ($
				getjson[$j] [' pm2_5 ']==0) {continue;
					} else{$count + +;
					$sum + + $getJson [$j] [' pm2_5 '];
				$PM 2_5= $sum/$count;
				} else{//insert into the MySQL $result [' City ']= $getJson [$i] [' area '];
				$result [' Pm25 ']=intval ($pm 2_5);
				$query = "INSERT into PM25 (CITY,PM25) VALUES ('". $result [' City ']. "'," $result [' pm25 ']. ")";
				mysql_query ($query);
			Break
}} return $getJson;

 }//func write_db $mem-> Close ();?>