使用@符号进行MySQL全文搜索会产生错误"语法错误,意外'@',期待$ end"

Question

由于@(在符号处),以下查询导致错误.删除后,查询将正常工作.我试图逃避@角色,但没有运气.

SELECT * FROM clients WHERE MATCH (form) AGAINST ('test@test.com' IN BOOLEAN MODE);

产生的错误是:

#1064 - syntax error, unexpected '@', expecting $end

请注意,我正在phpMyAdmin SQL控制台区域中测试这些查询,因此我的其他编程不会出现转义错误.

MySQL服务器是5.6.17版.

有任何想法吗？谢谢.

Answer 1

这与INNODB FULLTEXT索引相关联.

它是作为以下组合引入的:

1. InnoDB全文搜索不支持在单个搜索词上使用多个运算符

2. @distance此运算符仅适用于InnoDB表.它测试两个或多个单词是否都在相互指定的距离内开始,用单词测量.

http://dev.mysql.com/doc/refman/5.6/en/fulltext-boolean.html

# Running a test search for MATCH('+test{$ascii}test' IN BOOLEAN MODE) on all ASCII chars returns errors on:
40 (
41 )
64 @

MYSQL似乎将这些符号视为wordbreaks并且我发现无法逃脱并将其包含在实际查询中,因此我的解决方案是在符号上拆分并将它们作为一组包含在内,例如"test @ bar"==(+ test +巴)

# As a further test, running a search for MATCH('+{$ascii}' IN BOOLEAN MODE) returns errors for:
40 (
41 )
42 *
43 +
45 -
60 <
62 >
64 @
126 ~

这与MYSQL文档中的预期一样,是特殊的BOOLEAN修饰符

# As a testcase (Requires MYSQL 5.6+): 
CREATE TABLE `fulltext_innodb` (
`id` int(11) NOT NULL AUTO_INCREMENT,
 `text` text COLLATE utf8_unicode_ci,
 PRIMARY KEY (`id`),
 FULLTEXT KEY `text` (`text`)
) ENGINE=InnoDB
INSERT INTO `fulltext_innodb` (`id`, `text`) VALUES (1, 'test@bar');

SELECT * FROM `fulltext_innodb` WHERE MATCH (`text`) AGAINST( '+test@bar’ IN BOOLEAN MODE )

#1064 - syntax error, unexpected '@', expecting $end

Answer 2

不是直接的答案，但如果有人正在寻找 PHP 代码来处理用户输入搜索字符串的标记化以进行全文搜索，可以使用以下代码：

/**
 * Method to take an input string and tokenize it into an array of words for Full Text Searching (FTS).
 *
 * This method is used when an input string can be made up of multiple words (let's say, separated by space characters),
 * and we need to use different Boolean operators on each of the words. The tokenizing process is similar to extraction
 * of words by FTS parser in MySQL. The operators used for matching in Boolean condition are removed from the input $phrase.
 * These characters as of latest version of MySQL (8+) are: +-><()~*:""&|@  (@ is specific for InnoDB)
 * We can also execute the following query to get updated list: show variables like 'ft_boolean_syntax';
 * Afterwards, the modified string is split into individual words considering either space, comma, and, period (.) characters.
 * Details at: https://dev.mysql.com/doc/refman/8.0/en/fulltext-natural-language.html
 *
 * @param string $phrase Input statement/phrase consisting of words
 * @return array Tokenized words
 * @author Madhur, 2019
 */
function tokenizeStringIntoFTSWords(string $phrase) : array {
    $phrase_mod = trim(preg_replace('/[><()~*:"&|@+-]/', ' ', trim($phrase)));
    $words_arr = preg_split('/[\s,.]/', $phrase_mod, null, PREG_SPLIT_NO_EMPTY);

    // filter out the fulltext stop words and words whose length is less than 3.
    $fts_words = array();
    $fulltext_stop_words = array(
        'about','are','com','for','from','how','that','this','was','what',
        'when','where','who','will','with','und','the','www'
    );
    foreach($words_arr as $word) {
        // By default MySQL FULLTEXT index does not store words whose length is less than 3.
        // Check innodb_ft_min_token_size Ref: https://dev.mysql.com/doc/refman/8.0/en/innodb-parameters.html#sysvar_innodb_ft_min_token_size
        // So we need to ignore words whose length is less than 3.
        if(strlen($word) < 3) continue;

        // Ignore the fulltext stop words, whose length is greater than 3 or equal to 3.
        // Ref: https://dev.mysql.com/doc/refman/8.0/en/fulltext-stopwords.html
        if (in_array($word, $fulltext_stop_words)) continue;

        $fts_words[] = $word;
    }

    return $fts_words;
}

上面的代码也将处理停用词、最小字长限制和布尔模式运算符。因此，例如，如果用户输入: Search@bar with in Javascript，它将返回一个(Search, bar, Javascript). 之后，可以使用此数组编写全文查询。