mysql - 如何使用多个标准从数据库中查找值？

Question

我想根据其他三个字段中的信息从单个字段中检索数据。例如，如果我有一个包含以下字段的表格：宽度、长度、高度、重量和颜色。我想获取宽度 = $value 和长度 = $value2 和高度 = $value 的字段颜色的值。

Answer 1

select color from table_name where width = $value and length = $value2 and height = $value3

我假设您的意思是使用 SQL....

Answer 2

SQL几乎就是您在问题中写的！

select color from yourtable
     where width = $value and length = $value2 and height = $value

PHP：

$result = $mysqli->query("SELECT color FROM yourtable WHERE width = $value AND length = $value2 AND height = $value");

Answer 3

select 'singleFieldName' from table where width = $value AND length = $value2 AND height = $value3

Answer 4

试试这个

    echo $query = "select color from yourtable_name
        where width = '".$value1."' and length = '".$value2."' and height = '".$value3."'";