☒ the authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper. Sql是一种用于处理数据的语言，就像我们说的汉语、英语一样，有特定的语法结构，让我们灵活地处理数据。 sql并不难学，首先得理解 s q l 三个字母分别代表什么。 structured query. 欢迎大家持续关注invisor学术科研！喜欢记得 点赞收藏转发！双击屏幕解锁快捷功能~ 如果大家对于 「sci/ssci期刊论文发表」「scopus 、 cpci/ei会议论文发表」「名校科研助理申请」.
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