php - SQL计数错误

Question

我正在尝试使用计数函数来显示有多少员工的头衔为“销售”

if( !$connect)
{
die("ERROR: Cannot connect to database $db on server $server
using user name $user (".mysqli_connect_errno().
", ".mysqli_connect_error().")");
}
else
{
$userQuery = "COUNT(empID) FROM personnel WHERE jobTitle='Sales'";

$result = mysqli_query($connect, $userQuery);

if (!$result)
{
    die("Could not successfully run query ($userQuery) from $db: " . 
mysqli_error($connect) );
}

if (mysqli_num_rows($result) == 0)
{
    print("No records found with query $userQuery");
}
else
{
     print("<h1>SALES STAFF REPORT</h1>");
     while ($row = mysqli_fetch_assoc($result))
    {
        print("<p>There are 
        ".$row['COUNT(empID)']."</p>");
    }

}
 mysqli_close($connect);   // close the connection
}
?>

我收到此错误:

You have an error in your SQL syntax; check the manual that corresponds to your MariaDB server version for the right syntax to use near 'COUNT(empID) FROM personnel WHERE jobTitle='Sales'' at line 1

在这一行:

$userQuery = "COUNT(empID) FROM personnel WHERE jobTitle='Sales'";

我不确定我做错了什么，但我们将不胜感激。

最终结果应为“有 4 名销售人员”。

我的教授确实将其包含在作业中，不确定这是否有帮助。

"There are two different MySQL functions that you can use here: you can 
modify the SELECT statement to use a MySQL aggregation function,
or you can use the MySQL function that returns the number of records in the 
result set. "

Answer 1

您在创建该语句时缺少 SELECT 关键字。

你有:$userQuery = "COUNT(empID) FROM 人员 WHERE jobTitle='Sales'";

应该是:$userQuery = "从人员中选择 COUNT(empID) WHERE jobTitle='Sales'";