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要获取mysql 数据库表的多少条数据 怎么写。。。用pdo


回复讨论(解决方案)

$pdo = new PDO('127.0.0.1', username, password, dbname);$pdo->query("select count(*) from table_name");


直接用count(*)执行sql就行吧

关键是没看懂你的意思。你可以再把需求描述的详细一点。什么多少条?

$pdo->query("select count(*) from table_name"); 怎么获取返回值???有几条数据。。

$r = $pdo->query("select count(*) as cnt from table_name")->fetch(PDO::FETCH_ASSOC);
echo $r['cnt'];

$r = $pdo->query("select count(*) from table_name")->fetch(PDO::FETCH_NUM);
echo $r['cnt'];

php5.4.x 还可以写作
echo $pdo->query("select count(*) as cnt from table_name")->fetch(PDO::FETCH_ASSOC)['cnt'];

echo $pdo->query("select count(*) from table_name")->fetch(PDO::FETCH_NUM)[0];

$pdo->query("select count(*) from table_name"); 怎么获取返回值???有几条数据。。

用一个变量去接收,即
$data = $pdo->query("select count(*) from table_name");
$data应该是数组类型的数据!

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