Question

我有多个具有相同结构的mysql表。我试图用一个查询显示所有表的所有结果。我现在在网上搜索了几个小时，这就是我想出来的。

    $videos_query = mysql_query("SELECT 
                    table1.title,
                    table1.url,
                    table1.image,
                    table2.title,
                    table2.url,
                    table2.image,
                    table3.title,
                    table3.url,
                    table3.image
                 FROM
                    table1
                 INNER JOIN table2 ON table1.url = table2.url
                 INNER JOIN table3 ON table1.url = table3.url");
while($video_info = mysql_fetch_array($videos_query)){

然而，在PHP中使用上面的代码我得到错误“警告：mysql_fetch_array（）期望参数1是资源，布尔给定”

Answer 1

您的SQL查询中有错误 - table1必须为table2：

$videos_query = mysql_query("SELECT 
                    table1.title,
                    table1.url,
                    table1.image,
                    table2.title,
                    table2.url,
                    table2.image,
                    table3.title,
                    table3.url,
                    table3.image
                 FROM
                    table1
                 INNER JOIN table2 ON table1.url = table2.url
                 INNER JOIN table3 ON table1.url = table3.url");

if (mysql_num_rows($videos_query) > 0) {
    while ($video_info = mysql_fetch_array($videos_query)) {
        // process your data here
    }
}

如果你想做工会选择：

$videos_query = mysql_query("
  SELECT title, url, image
  FROM table1
  UNION
  SELECT title, url, image
  FROM table2
  UNION
  SELECT title, url, image
  FROM table3
");

if (mysql_num_rows($videos_query) > 0) {
    while ($video_info = mysql_fetch_array($videos_query)) {
        // process your data here
    }
}

此外，您可能希望按某些列进行排序 - 然后添加ORDER BY + column_name。

Answer 2

更改

 INNER JOIN table2 ON table1.url = table1.url

到

INNER JOIN table2 ON table1.url = table2.url

Answer 3

在检查ON时，您正在比较不正确的table1.url = table1.url。

这是正确的代码：

$videos_query = mysql_query("SELECT 
                table1.title,
                table1.url,
                table1.image,
                table2.title,
                table2.url,
                table2.image,
                table3.title,
                table3.url,
                table3.image
             FROM
                table1
             INNER JOIN table2 ON table1.url = table2.url
             INNER JOIN table3 ON table1.url = table3.url");
while($video_info = mysql_fetch_array($videos_query)){

使用php显示来自多个mysql表的结果

3 个答案: