小項目有時需要用到關鍵詞搜索相關性排序，用sphinx顯得殺雞用牛刀，就用mysql的order by對付下。
方法一：

復制代碼 代碼如下:

select * from articles where (title LIKE '%keywords%') or (content LIKE '%helloworld%') order by ((CASE WHEN title LIKE '%keywords%' THEN 2 ELSE 0 END) + (CASE WHEN content LIKE '%helloworld%' THEN 1 ELSE 0 END)) ASC, dateline DESC

復制代碼 代碼如下:

$kw = preg_replace("/(/s+)|(　+)+/","", $kw);//替代空格,換行,tab,中文空格
$kw = preg_replace( "/(^/s*)|(/s*$)/ ", "",$kw);//去除首尾空格
$kw = preg_replace("/(/s+)/", "", $kw);//替換多個空格為一個空格
$q = explode('',$kw);//枚舉關鍵字

然后是生成SQL語句的代碼

復制代碼 代碼如下:

$f = array(”name”,”description”); //查詢的字段name=產品名,description=產品描述
$s = array(4,2); //權重,name字段匹配積分4分，description字段匹配積2分，最后按積分排序

復制代碼 代碼如下:

//創建查詢條件語句
for($i=0;$i<count($q);$i++){
for($j=0;$j<count($f);$j++){
$clause[$c] = ” (”.$f[$j].” LIKE ‘%”.$q[$i].”%') “;
$score[$c] = ” IF(LOCATE('”.$q[$i].”‘, “.$f[$j].”), “.$s[$j].”, 0) “;
$c++;
}
}
$sql = “SELECT id, name, description,
(”.implode(”+”,$score).”) AS score
FROM product
WHERE (”.implode(” OR “,$clause).”)
ORDER BY score DESC”;