How can I return unique rows when using an INNER JOIN in MySQL?
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I have 3 tables: links, keywords, and keywords_links. A link can have multiple keywords, and multiple links can have the same keyword. `keywords_links` is used to join `links` and `keywords`.
When I run the following query, multiple rows of the same link is returned because multiple keywords match. How can I modify this query to return unique rows?

    SELECT links . * 
    FROM  `links` 
    INNER JOIN keywords_links ON keywords_links.link_id = id
    INNER JOIN keywords ON keywords.id = keywords_links.keyword_id
    WHERE keywords.keyword
    IN (
    'php', 'sql', 'html', 'css'
    )