MySQL连接三个表并搜索在一个表中找到的几个关键字

Question

我试图通过避免包含相同单词的多个记录来限制数据库的大小，因此我建立了两个表，用于将关键字与其他表中的行相关联。

例如，我们使用以下搜索输入：“找到我”

希望得到什么，这是product_id = 106中的product_name。我可以仅搜索产品名称吗？ 否，因为产品可以与其他关键字（不属于product_name的一部分）相关联。

表格：ec_products

product_id    | product_name    | is_deleted
---------------------------------------------
106           | some product    | 0

表格：ec_keywords_index

word_id       | keyword
---------------------------------------------
55            | find
61            | my
77            | product

表格：ec_keyword_relations

word_id       | application_id    | related_id
------------------------------------------------
55            | 1                 | 106
61            | 1                 | 106
77            | 1                 | 106

因此，当我在搜索输入中输入“ find my”时，我现在想要的是：

• 我只想要ec_keyword_relations.application_id = 1的匹配
• 我的搜索字符串中的所有单词都应与产品有关。 例如，如果我将搜索输入更改为“查找裤子”，则不应找到product_id = 106。

这是到目前为止我已经尝试过的方法（并且我知道我暂时还没有一个可行的解决方案）：

    $searchInput = 'find my';
    $keywords = explode(' ', $searchInput);

    $keyword_count = count($keywords);

    $n = 1;
    $query = '';

    foreach($keywords as $keyword) { 
        if ($n !== $keyword_count) { 
            $query_ext = ' AND ';
        } else { 
            $query_ext = ''; 
        } 

        $query .= "(ec_keywords_index.keyword LIKE '%$keyword%')" . $query_ext;

        ++$n;
    }

    $query = "
        SELECT 
            ec_products.product_name

        FROM 
            ec_products

        LEFT JOIN ec_search_word_relations
            ON ec_keyword_relations.related_id = ec_products.product_id

        LEFT JOIN ec_keywords_index
            ON ec_keywords_index.word_id = ec_keyword_relations.word_id

        WHERE 
            ($query) 
        AND 
            ec_products.is_deleted = '0' 
        AND 
            ec_keyword_relations.application_id = '1'

        GROUP BY
            ec_products.product_id

        ORDER BY 
            ec_products.product_name ASC 

        LIMIT 
            100";

    $stmt = $mysqli->prepare($query);
    $stmt->execute();
    $stmt->store_result();
    $stmt->bind_result($name);
    while ($stmt->fetch()) {
        echo $name;
    }

更新：

经过一番摆弄之后，我想出了可以按预期工作的解决方案。 （就性能而言）是好的还是坏的解决方案？

    $searchInput = 'find my';
    $keywords = explode(' ', $searchInput);

    $keyword_count = count($keywords);

    $n = 1;
    $where_query = '';
    $having_query = '';

    foreach($keywords as $keyword) { 
        if ($n != $keyword_count) {
            $w_query_ext = ' OR '; 
            $h_query_ext = ' AND ';
        } else { 
            $w_query_ext = ''; 
            $h_query_ext = ''; 
        }

        $where_query .= "ec_keywords_index.keyword LIKE '%" . $keyword . "%'" . $w_query_ext;

        $having_query .= "related_keywords LIKE '%" . $keyword . "%'" . $h_query_ext;

        ++$n;
    }

    $query = "
        SELECT 
            ec_products.product_name, 
            GROUP_CONCAT(' ', ec_keywords_index.keyword) AS 'related_keywords'

        FROM 
            ec_products, 
            ec_keywords_index

        LEFT JOIN 
            ec_keyword_relations 
            ON ec_keyword_relations.word_id = ec_keywords_index.word_id

        WHERE ($where_query) 
            AND ec_products.product_id = ec_keyword_relations.related_id 
            AND ec_keyword_relations.application_id = '1' 
            AND ec_products.is_deleted = '0'

        GROUP BY 
            ec_products.product_name

        HAVING 
            ($having_query)

        LIMIT 
            100";

    $stmt = $mysqli->prepare($query);
    $stmt->execute();
    $stmt->store_result();
    $stmt->bind_result($name);
    while ($stmt->fetch()) {
        echo $name;
    }

上面的示例输出如下查询：

    SELECT 
        ec_products.product_name, 
        GROUP_CONCAT(' ', ec_keywords_index.keyword) AS 'related_keywords'

    FROM 
        ec_products, 
        ec_keywords_index

    LEFT JOIN 
        ec_keyword_relations 
        ON ec_keyword_relations.word_id = ec_keywords_index.word_id

    WHERE (ec_keywords_index.keyword LIKE '%find%' OR ec_keywords_index.keyword LIKE '%my%') 
        AND ec_products.product_id = ec_keyword_relations.related_id 
        AND ec_keyword_relations.application_id = '1' 
        AND ec_products.is_deleted = '0'

    GROUP BY 
        ec_products.product_name

    HAVING 
        (related_keywords LIKE '%find%' AND related_keywords LIKE '%my%')

    LIMIT 
        100

我正在使用GROUP_CONCAT创建一个包含与产品相关的所有关键字的列，然后使用我的WHERE子句仅选择在搜索字符串中实际找到的关键字...然后使用HAVING子句在该列中进行搜索使用GROUP_CONCAT构建。

Answer 1

拥有示例的答案：

经过一番摆弄之后，我想出了可以按预期工作的解决方案。 我不知道这是否是最佳做法，但它就像一个魅力。

    $searchInput = 'find my';
    $keywords = explode(' ', $searchInput);

    $keyword_count = count($keywords);

    $n = 1;
    $where_query = '';
    $having_query = '';

    foreach($keywords as $keyword) { 
        if ($n != $keyword_count) {
            $w_query_ext = ' OR '; 
            $h_query_ext = ' AND ';
        } else { 
            $w_query_ext = ''; 
            $h_query_ext = ''; 
        }

        $where_query .= "ec_keywords_index.keyword LIKE '%" . $keyword . "%'" . $w_query_ext;

        $having_query .= "related_keywords LIKE '%" . $keyword . "%'" . $h_query_ext;

        ++$n;
    }

    $query = "
        SELECT 
            ec_products.product_name, 
            GROUP_CONCAT(' ', ec_keywords_index.keyword) AS 'related_keywords'

        FROM 
            ec_products, 
            ec_keywords_index

        LEFT JOIN 
            ec_keyword_relations 
            ON ec_keyword_relations.word_id = ec_keywords_index.word_id

        WHERE ($where_query) 
            AND ec_products.product_id = ec_keyword_relations.related_id 
            AND ec_keyword_relations.application_id = '1' 
            AND ec_products.is_deleted = '0'

        GROUP BY 
            ec_products.product_name

        HAVING 
            ($having_query)

        LIMIT 
            100";

    $stmt = $mysqli->prepare($query);
    $stmt->execute();
    $stmt->store_result();
    $stmt->bind_result($name);
    while ($stmt->fetch()) {
        echo $name;
    }

上面的示例输出如下查询：

    SELECT 
        ec_products.product_name, 
        GROUP_CONCAT(' ', ec_keywords_index.keyword) AS 'related_keywords'

    FROM 
        ec_products, 
        ec_keywords_index

    LEFT JOIN 
        ec_keyword_relations 
        ON ec_keyword_relations.word_id = ec_keywords_index.word_id

    WHERE (ec_keywords_index.keyword LIKE '%find%' OR ec_keywords_index.keyword LIKE '%my%') 
        AND ec_products.product_id = ec_keyword_relations.related_id 
        AND ec_keyword_relations.application_id = '1' 
        AND ec_products.is_deleted = '0'

    GROUP BY 
        ec_products.product_name

    HAVING 
        (related_keywords LIKE '%find%' AND related_keywords LIKE '%my%')

    LIMIT 
        100

我正在使用GROUP_CONCAT创建一个包含与产品相关的所有关键字的列，然后使用我的WHERE子句仅选择在搜索字符串中实际找到的关键字...然后使用HAVING子句在该列中进行搜索使用GROUP_CONCAT构建。