php - 操作'UNION'的排序规则(utf8_general_ci，IMPLICIT)和(utf32_general_ci，IMPLICIT)的非法混合

我在dbase按多选列表中有用于搜索的代码当我选择一个选项时，出现以下错误：
排序规则（utf8_general_ci，IMPLICIT）和
（utf32_general_ci，隐式）用于操作“UNION”
问题在哪里？
这是我的代码：

<?php
$expertsearch = trim($_GET['nm']);

include("connect.php");

mysql_query("SET NAMES utf8");

$expertdata = mysql_fetch_object(mysql_query("SELECT * FROM experts WHERE ID = $expertsearch"));
$expertname = $expertdata->expert_name;

$sql = "SELECT * FROM eridb WHERE
eridb.expert1 = $expertsearch OR eridb.expert2 = $expertsearch OR eridb.expert3 =  $expertsearch UNION

SELECT * FROM kacaredb WHERE
kacaredb.expert1 = $expertsearch OR kacaredb.expert2 = $expertsearch OR kacaredb.expert3     = $expertsearch UNION

SELECT * FROM mwedb WHERE
mwedb.expert1 = $expertsearch OR mwedb.expert2 = $expertsearch OR mwedb.expert3 =     $expertsearch UNION

SELECT * FROM secdb WHERE
secdb.expert1 = $expertsearch OR secdb.expert2 = $expertsearch OR secdb.expert3 =     $expertsearch UNION

SELECT * FROM seecdb WHERE
seecdb.expert1 = $expertsearch OR seecdb.expert2 = $expertsearch OR seecdb.expert3 =  $expertsearch ";

$res = mysql_query($sql);

echo "<table border='1'>

$count = 0;
while($row=mysql_fetch_object($res))
{
$count = $count+1;
echo "<tr>";
echo "<td>" . $count . "</td>";
echo "<td>" . $row->id . "</td>";
echo "<td>" . $row->nameofresearch . "</td>";
echo "<td>" . $row->dateofstart . "</td>";
echo "<td>" . $row->dateofend . "</td>";
echo "<td>" . $row->budget . "</td>";
echo "<td>" . $row->requestedby . "</td>";
echo "<td>" . $row->projectstatus . "</td>";
echo "<td>" . $expertname . "</td>";
echo "<td>" . $row->projectstatus . "</td>";
echo "</tr>";
}

if($res){
echo "Successful";
echo "<BR>";
}
else {
echo "ERROR";
echo "<br>";
echo mysql_error();
echo "<a href='main1.php'><br>Please try again </a>";
}
echo "</table>";
?>

最佳答案

有些列具有不同的字符集/排序规则，不能一起选择，在您的示例中是utf8和utf32。在表中找到这些列（运行SHOW CREATE TABLE语句），并尝试使用CONVERT函数对它们进行转换，例如-

SELECT CONVERT(column_name USING utf8) FROM experts
  UNION
SELECT CONVERT(column_name USING utf8) FROM eridb

关于php - 操作'UNION'的排序规则(utf8_general_ci，IMPLICIT)和(utf32_general_ci，IMPLICIT)的非法混合，我们在Stack Overflow上找到一个类似的问题：https://stackoverflow.com/questions/21275815/