Mysql中分页查询的两个解决方法比较

SELECT COUNT(*) FROM foo WHERE b = 1;
SELECT a FROM foo WHERE b = 1 LIMIT 100,10;

SELECT SQL_CALC_FOUND_ROWS a FROM foo WHERE b = 1 LIMIT 100, 10;
SELECT FOUND_ROWS();

CREATE TABLE IF NOT EXISTS `foo` (
`a` int(10) unsigned NOT NULL AUTO_INCREMENT,
`b` int(10) unsigned NOT NULL,
`c` varchar(100) NOT NULL,
PRIMARY KEY (`a`),
KEY `bar` (`b`,`a`)
) ENGINE=MyISAM;

<?php

$host = '192.168.100.166';
$dbName = 'test';
$user = 'root';
$password = '';

$db = mysql_connect($host, $user, $password) or die('DB connect failed');
mysql_select_db($dbName, $db);

 
echo '==========================================' . "\r\n";

$start = microtime(true);
for ($i =0; $i<1000; $i++) {
    mysql_query("SELECT SQL_NO_CACHE COUNT(*) FROM foo WHERE b = 1");
    mysql_query("SELECT SQL_NO_CACHE a FROM foo WHERE b = 1 LIMIT 100,10");
}
$end = microtime(true);
echo $end - $start . "\r\n";

echo '==========================================' . "\r\n";

$start = microtime(true);
for ($i =0; $i<1000; $i++) {
    mysql_query("SELECT SQL_NO_CACHE SQL_CALC_FOUND_ROWS a FROM foo WHERE b = 1 LIMIT 100, 10");
    mysql_query("SELECT FOUND_ROWS()");
}
$end = microtime(true);
echo $end - $start . "\r\n";

echo '==========================================' . "\r\n";

$start = microtime(true);
for ($i =0; $i<1000; $i++) {
    mysql_query("SELECT SQL_NO_CACHE COUNT(*) FROM foo WHERE b = 1");
    mysql_query("SELECT SQL_NO_CACHE * FROM foo WHERE b = 1 LIMIT 100,10");
}
$end = microtime(true);
echo $end - $start . "\r\n";

echo '==========================================' . "\r\n";

$start = microtime(true);
for ($i =0; $i<1000; $i++) {
    mysql_query("SELECT SQL_NO_CACHE SQL_CALC_FOUND_ROWS * FROM foo WHERE b = 1 LIMIT 100, 10");
    mysql_query("SELECT FOUND_ROWS()");
}
$end = microtime(true);
echo $end - $start . "\r\n";