ebe*_*ine 2 mysql join query-optimization
这是我的查询:
这看起来效率高吗?使用JOIN有优势吗?或者这是一样的吗?
$query_Recordset2 =
"SELECT cute_news.category, cute_news.id, cute_story.short, cute_story.post_id, cute_news.date, cute_news.url, cute_news.title
FROM cute_news, cute_story
WHERE cute_news.id = cute_story.post_id AND category LIKE '10%'
ORDER BY date DESC LIMIT 0,35";
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这个问题可能与那个问题重复.
隐式JOIN不具有意图,因此可读性较差.
您的查询将导致严格相同的结果:
SELECT cute_news.category, cute_news.id, cute_story.short, cute_story.post_id, cute_news.date, cute_news.url, cute_news.title
FROM cute_news
INNER JOIN cute_story ON cute_story.post = cute_news.id
WHERE category LIKE '10%'
ORDER BY date DESC LIMIT 0,35
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但后一个查询更具可读性,因为您将JOIN谓词与过滤器分开并表达查询背后的逻辑.
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