MySQL全文搜索不适用于某些单词

Question

I have made a MySQL full text search with min search length of 3 characters, search is working fine except for some words no results are return where result are available.

If i search for word avg results are returned., If i search for word how no result are returned.

I am trying this way.

$keyword = preg_replace('/  */', ' *', $keyword);
$keyword = preg_replace('/\s+/', ' *', $keyword);
$keyword = preg_replace('/\W+/', ' *', $keyword);
$keyword = "$keyword*";

$query = "SELECT *, MATCH (title, link) AGAINST ( ? IN BOOLEAN MODE) AS rel FROM $table WHERE MATCH (title, link) AGAINST ( ? IN BOOLEAN MODE) GROUP by rel DESC, $order $sort LIMIT $rpp OFFSET $offset";

I tried these solution too but same no result for word `how'

//Changing
$keyword = preg_replace('/  */', ' +', $keyword);
$keyword = preg_replace('/\s+/', ' +', $keyword);
$keyword = preg_replace('/\W+/', ' +', $keyword);

$keyword = preg_replace('/  */', '+', $keyword);
$keyword = preg_replace('/\s+/', '+', $keyword);
$keyword = preg_replace('/\W+/', '+', $keyword);

//In combination
$keyword = "+$keyword*";
$keyword = "$keyword*";    
$keyword = "+$keyword";
$keyword = "$keyword";

Please see and suggest why my search is not working on some words.

Thanks.

Update The word how is present in 10 rows, The word avg is present in 16 rows. I have more than 650 rows. I am using IN BOOLEN MODE in query too so there should be not problem about MySQL 50% rule to make how a stop word .

Answer 1

avg and how are both too short in standard configuration, see documentation . You changed that, but how is an element of the stop word list :

Boolean full-text searches have these characteristics:

The minimum and maximum word length full-text parameters apply.

The stopword list applies.

Override the stopword list with the ft_stopword_file system variable:

To override the default stopword list, set the ft_stopword_file system variable. (See Section 5.1.4, “Server System Variables”.) The variable value should be the path name of the file containing the stopword list, or the empty string to disable stopword filtering.