Question

我已经在网上寻找解决我问题的方法好几个小时但无济于事。

我有多个selct语句，从不同的mysql表接收数据。我希望回应完全分开的结果。目前，结果打印好像是一个，所以我不能单独处理答案。

假设表的输出为：

我想回应一下：

result1 = 100;
result2 = 200;

等

所以我可以在另一个程序中完成最终结果。如果结果为null，则不应产生错误，但只是发布0。例如，如果从mysql表输出：

100
null
null
100

我希望输出清晰显示

result1 = 100;
result2 = 0;
result3 = 0;
result4 = 100;

等

$check_sco = 100;

$sql = "SELECT TABLE_1 FROM RIDER_1 WHERE score1=$check_sco;";
$sql .= "SELECT TABLE_1 FROM RIDER_2 WHERE score1=$check_sco;";
$sql .= "SELECT TABLE_1 FROM RIDER_3 WHERE score1=$check_sco;";
$sql .= "SELECT TABLE_1 FROM RIDER_4 WHERE score1=$check_sco";


if (mysqli_multi_query($con,$sql)) {
    do {
        /* store first result set */
        if ($result = mysqli_store_result($con)) {
            while ($row = mysqli_fetch_row($result)) {
                printf("%s\n", $row[0]);//how to echo separated result that can be manipulated indepedently?
        }
        mysqli_free_result($result);
    }

} while (mysqli_next_result($con));

}

谢谢。

Answer 1

你需要使用IFNULL如果TABLE_1不为null，它将返回TABLE_1，否则它会给你0

SELECT IFNULL(TABLE_1, 0) FROM RIDER_1 WHERE score1=$check_sco;
SELECT IFNULL(TABLE_1, 0) FROM RIDER_2 WHERE score1=$check_sco;
SELECT IFNULL(TABLE_1, 0) FROM RIDER_3 WHERE score1=$check_sco;
SELECT IFNULL(TABLE_1, 0) FROM RIDER_4 WHERE score1=$check_sco

Answer 2

为什么不按顺序运行它们？

$check_sco = 100;

$riders = array();
for($i=1; $i<=4; $i++) {
    $sql = "SELECT TABLE_1 FROM RIDER_" . $i . " WHERE score1=" . $check_sco;
    $result = mysqli_query($con, $sql);
    $row = $result->fetch_assoc();
    $riders[] = ($row['TABLE_1']) ? $row['TABLE_1'] : 0;
}

然后你会得到一个包含你想要的结果的数组

多个Mysqli Select语句，回显分离结果

2 个答案: