SQL在PHP中不起作用
我在这里有点困惑,无论我尝试什么,我都无法得到一个简单的SQL语句来为我返回正确的结果 例如,这个例子非常有效:SQL在PHP中不起作用,php,mysql,Php,Mysql,我在这里有点困惑,无论我尝试什么,我都无法得到一个简单的SQL语句来为我返回正确的结果 例如,这个例子非常有效: $sql = mysqli_fetch_assoc(mysqli_query(mysqli_connect('127.0.0.1','root','','recruitment'), "SELECT COUNT(`id`) as 'result' FROM {$table} WHERE {$field} {$operator} {$value}")); 然而,当我使用类似的方法处理
$sql = mysqli_fetch_assoc(mysqli_query(mysqli_connect('127.0.0.1','root','','recruitment'), "SELECT COUNT(`id`) as 'result' FROM {$table} WHERE {$field} {$operator} {$value}"));
然而,当我使用类似的方法处理这个问题时,我得到了一个空结果
function coExists($name){
$con = mysqli_connect('localhost','root','','rec_spec');
$sql = mysqli_fetch_assoc(mysqli_query($con, "SELECT COUNT(`id`) AS 'result' FROM `companies` WHERE `name`='.$name.'"));
//return $sql['result']; <--Returns zero
print_r($sql); // <--Returns Array ( [result] => 0 )
}
函数共存($name){
$con=mysqli_connect('localhost','root','rec_spec');
$sql=mysqli\u fetch\u assoc(mysqli\u query($con,“选择COUNT(`id`)作为`companys`的`result',其中`name`='.$name.''”);
//返回$sql['result'];运行此函数,查看服务器的配置,并检查mysqli是否已安装
<?php
echo phpinfo();
?>
更改您的查询
$sql = mysqli_fetch_assoc(mysqli_query($con, "SELECT COUNT(`id`) AS 'result' FROM `companies` WHERE `name`='.$name.'"));
到
$sql=mysqli\u fetch\u assoc(mysqli\u查询($con,“从'companys'中选择COUNT(`id`)作为'result',其中'name`='$name');
函数共存($name){
$con=mysqli_connect('localhost','root','rec_spec');
$sql=mysqli\u fetch\u assoc(mysqli\u查询($con,“选择COUNT(`id`)作为`companys`的`result',其中`name`='$name');
//返回$sql['result'];因为'result'
错误。列名别名是标识符,属于反勾号。并且='.$name'"
不是有效的字符串连接,因为所有内容都已在双引号内插入。此外,谷歌搜索参数绑定,然后切换到PDO。您在第二组代码中定义的数据库与第一组代码中定义的数据库不同。是的,我指的是不同的数据库,这是因为一组代码在一个DB上工作得非常好第二个总是返回零。如果我切换到无连接或{$name},则得到-警告:mysqli_fetch_assoc()期望参数1是mysqli_result,布尔值在…Error中给出
$sql = mysqli_fetch_assoc(mysqli_query($con, "SELECT COUNT(`id`) AS 'result' FROM `companies` WHERE `name`='.$name.'"));
$sql = mysqli_fetch_assoc(mysqli_query($con, "SELECT COUNT(`id`) AS 'result' FROM `companies` WHERE `name`='$name'"));
function coExists($name){
$con = mysqli_connect('localhost','root','','rec_spec');
$sql = mysqli_fetch_assoc(mysqli_query($con, "SELECT COUNT(`id`) AS 'result' FROM `companies` WHERE `name`='$name'"));
//return $sql['result']; <--Returns zero
print_r($sql); // <--Returns Array ( [result] => 0 )
}