6. 7 约束等级Cascade方式：在父表上update/delete记录时，同步update/delete掉子表的匹配记录Set null方式：在父表上update/delete记录时，将子表上匹配记录的列设为null，但是要注意子表的外键列不能为not nullNo action方式：如果子表中有匹配的记录，则不允许对父表对应候选键进行update/delete操作Restrict方式：同....

文章 2023-07-13 来自：开发者社区

MySQL数据库，从入门到精通：第十三篇——MySQL数据表约束详解（三）

5. 自增列：AUTO_INCREMENT5. 1 作用某个字段的值自增5. 2 关键字auto_increment5. 3 特点和要求（ 1 ）一个表最多只能有一个自增长列（ 2 ）当需要产生唯一标识符或顺序值时，可设置自增长（ 3 ）自增长列约束的列必须是键列（主键列，唯一键列）（ 4 ）自增约束的列的数据类型必须是整数类型（ 5 ）如果自增列指定了 0 和 null，会在当前最大值的基础上....

文章 2023-07-13 来自：开发者社区

MySQL数据库，从入门到精通：第十三篇——MySQL数据表约束详解（一）

前言在MySQL数据库中，约束是一种对数据表中数据进行限制和检查的方法，可以保证数据表中数据的完整性和一致性。本文将深入剖析MySQL中的各种约束，包括非空约束、唯一性约束、主键约束、自增列、外键约束、默认值约束以及CHECK约束等等，同时结合开发场景给出约束使用和实践的技巧和方法，帮助读者更好地掌握MySQL中数据表相关操作的技巧和方法。摘要本文将主要分为9个部分，分别对MySQL中的各种约束....

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满足等保2.0二级和三级 “安全审计”合规要求的同时，智能解析数据库通信流量，细粒度审计数据库访问行为，通过对数据库全量行为的审计溯源、危险攻击的实时告警、风险语句的智能预警，提供数据库资产最安全的监控保障。

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