Question

我在while循环中有这个函数，由于某种原因它说所有记录都是重复的。

我试过了：

$tst->RecordCount() === 1
$tst->RecordCount() == 1
$tst->RecordCount() = 1

$tst->RecordCount() === '1'
$tst->RecordCount() == '1'
$tst->RecordCount() = '1'

$tst->RecordCount() === "1"
$tst->RecordCount() == "1"
$tst->RecordCount() = "1"

但似乎没有工作

        $sql45 = "SELECT 
                count(*)
            FROM
                companies 
            WHERE 
                MC = " . $test;
    $tst = $conn->Execute($sql45);
    if ($tst === false) die("horrible death:" . $conn->ErrorMsg() . " SQL: " . $sql45); 

   if($tst->RecordCount() === 1){
        echo $test . "<br>";
        echo "Duplicate record <br>";
        continue;

    }

这是我收到的

545481
Duplicate record 
45
Duplicate record 
11111

Answer 1

你的记录数总是1.你有

SELECT count(*) FROM companies WHERE MC = somevalue

这总是返回一行，即记录计数为1.也许它是你想要得到的计数的值？

Answer 2

您可以使用以下方法检查是否存在行：

SELECT EXISTS(SELECT 1 FROM table1 WHERE ...)

它比计数（*）更有效。希望它有所帮助。

检查RecordCount（）是否存在记录

2 个答案: