php 如何计算查询结果行数？
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How do I count query result rows?
提问by Tom van der Woerdt
What should I replace 'CODE TO VERIFY IF QUERY RESULT ROW IS = 1' for?
I've tried many ways using num_rows but it won't work.
My PHP code:
我应该用什么替换“如果查询结果行是 = 1 的代码来验证”？
我已经尝试了很多使用 num_rows 的方法，但它不起作用。
我的PHP代码：
$con=mysqli_connect("localhost","mbrconsu_un394x","y1cz9,rd+hf6","mbrconsu_mmx");
if (mysqli_connect_errno($con))
{
echo "Failed to connect to MySQL: " . mysqli_connect_error();
}
$usuario = $con->real_escape_string($_GET['usuario']);
$senha = $con->real_escape_string($_GET['senha']);
$query = mysqli_query($con, "SELECT * FROM 'login' WHERE usuario = '$usuario' AND senha='$senha'");
if(CODE TO VERIFY IF QUERY RESULT ROW IS = 1){
while($row = mysqli_fetch_assoc($query)){
$db_username = $row['usuario'];
$db_password = $row['senha'];
}
if($usuario == $db_username && $senha == $db_password){
return true;
}
} else {
return false;
}
mysqli_close($con);
?>
回答by Tom van der Woerdt
$query->num_rows;
or
或者
mysqli_num_rows($query);
回答by Farhad
Also you can use this sql query :
你也可以使用这个 sql 查询：
Select count(*) from table
回答by Bradley Kovacs
you could just do
你可以做
if($row = mysqli_fetch_assoc($query)) {
}
also you may want to save your username and password in one file as constants
您也可能希望将您的用户名和密码作为常量保存在一个文件中
回答by Mansour Babasafari
You can use:
您可以使用：
$stmt=$mysqli->prepare("select `id` from `agahicustomer` where `city`=?");
$stmt->bind_param("s",$cityid);
$stmt->execute();
$stmt->store_result();
$stmt->bind_result($id);
return $stmt->affected_rows;
$stmt->close();
