protected $searchable = [
        /**
         * Columns and their priority in search results.
         * Columns with higher values are more important.
         * Columns with equal values have equal importance.
         *
         * @var array
         */
        'columns' => ['title' => 10,
            'intro' => 5,
            'body' => 2,
        ]
    ];

select `id`, `title` from (select `posts`.*, max ((case when LOWER (`title`) LIKE 'id' then 150 else 0 end) 
+ (case when LOWER (`title`) LIKE 'id%' then 50 else 0 end) 
+ (case when LOWER (`title`) LIKE '%id%' then 10 else 0 end)

+ (case when LOWER (`intro`) LIKE 'id' then 75 else 0 end) 
+ (case when LOWER (`intro`) LIKE 'id%' then 25 else 0 end) 
+ (case when LOWER (`intro`) LIKE '%id%' then 5 else 0 end) 

+ (case when LOWER (`body`) LIKE 'id' then 30 else 0 end) 
+ (case when LOWER (`body`) LIKE 'id%' then 10 else 0 end) 
+ (case when LOWER (`body`) LIKE '%id%' then 2 else 0 end)) 
as relevance from `posts` group by `posts`.`id` 
having relevance >= 5.25 order by `relevance` desc) as `posts`

• 1.search ($query_str, $threshold = null, $entireText = false, $entireTextOnly = false);

• 2.$threshold=null 时，则 $threshold= (10 + 5 + 2) /4 = 4.25, 当 $threshold 设的越高，匹配度就越高。

• 3. 当 $query_str 中含有空格时，会分开匹配各字符串。

• 4.LIKE '%id%' 则，relevance 1;LIKE 'id%' 则，relevance 5;LIKE 'id' 则，relevance * 15;

• 5. 当匹配整个字符串，LIKE 'id hello' 则 relevance 50;LIKE '%id hello%' 则 relevance 30;

• 5.$entireText=true, 表示当 $query_str 有空格时，优先匹配整个字符串

• 6.$entireTextOnly =true, 当 $query_str 有空格时，表示只匹配整个字符串，匹配 $query_str 与 %$query_str%

https://github.com/nicolaslopezj/searchable