Split complex tasks into simpler subtasks 将复杂任务分解为较简单的子任务 Just as it is good practice in software engineering to decompose a complex system into a set of modular components, the same is true of tasks submitted to GPTs. Complex tasks tend to …
alter table 表名 drop CONSTRAINT 主键约束
alter table 表名 alter column 字段1 varchar(16)not null
alter table 表名 add CONSTRAINT 主键约束 primary key(字段1,字段2) 主键约束名字可以在CONSTRAINT查看
介绍
有时我们为了测试方便,会去除主键和添加主键,我们可以用下面的SQL语句进行修改
例
下面给user表的id字段添加主键
ALTER TABLE user ADD PRIMARY KEY (id);下面给user表的id字段移除主键
alter table user modify id varchar(255)或
alter ta…