我有一个包含 4 个字段的数据库,我想通过多个 OR 条件从该数据库中搜索用户,问题是如何根据 true 或条件的数量索引选择。字段是课程,学校,学院,城市我希望结果应该根据 true 或条件的数量显示,这里是代码
<?php
$con = mysql_connect("xxx.xx.xxx.xxx","myusername","mypassword");
if (!$con)
{
die('Could not connect: ' . mysql_error());
}
mysql_select_db("character", $con);
$searchfrnd = mysql_query("SELECT * FROM user WHERE (course='physics' or school='st thomas' or college='mit' or city='austin'))");
WHILE($display = mysql_fetch_array($searchfrnd))
{
$frnd=$display[userid];
echo $frnd;
}
?>
- 我只希望显示的结果的优先级应该是真实OR条件数量的递减顺序。换句话说,按照匹配值数量的递减顺序
你可以做这样的事情
select (case when surname = 'jack' then 1 else 0 end +
case when school ='st' then 1 else 0 end +
case when college='mit' then 1 else 0 end +
case when city='austin' then 1 else 0 end) as score,
*
from
user
WHERE surname='jack' or
school='st' or
college='mit' or
city='austin')
order by score desc;
尝试以下查询:
SELECT *
FROM user
WHERE surname='jack'
OR school='st'
OR college='austin'
OR city='mit'
ORDER BY (
IF(surname='jack', 1, 0)
+ IF(school='st', 1, 0)
+ IF(college='austin' , 1, 0)
+ IF(city='mit', 1, 0)
) DESC;