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文章 2024-07-21 来自：开发者社区

MySQL设计规约问题之为什么应该把字段定义为NOT NULL并且提供默认值

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问答 2024-04-24 来自：开发者社区

在SQL中，为什么应该把字段定义为NOT NULL并且提供默认值？

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阿里云文档 2022-05-26

SQL效检失败报错ODPS-0130121,[1,122]Invalidargumenttype-invalidtypeINTofargument1forfunctionDATEDIFF,expectDATETIME

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问答 2021-10-16 来自：开发者社区

请问在SQL中如何定义NULL值，Blank Space(空格)和ZERO（0）？

问答 2021-10-02 来自：开发者社区

SQL-字段为什么要求定义为not null？

字段为什么要求定义为not null？

问答 2021-09-30 来自：开发者社区

SQL中如何定义NULL值，Blank Space(空格)和ZERO（0）？

如何定义NULL值，Blank Space(空格)和ZERO（0）？

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更新时间 2024-07-22 08:47:04

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