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MySQL：查询字段数量多少对查询效率的影响

发表于:2026-04-01

这个问题是最近在分析一个SQL时发起的疑问，然后请教高鹏(重庆八怪)老师，八怪老师予以解答，特此转载老师的文章(本文内容格式略有调整)。这个问题是最近在分析一个SQL时发起的疑问，然后请教高鹏(重庆八怪)老师，八怪老师予以解答，特此

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