long2020

摘要： 创建表外键--切记：作为外键一定要和关联主键的数据类型保持一致create table student( id int primary key auto_increment, name varchar(20), charger_id tinyint, foreign key (charger_id) 阅读全文

摘要： use table_name ==切换表 插入数据insert into table_name (field1,field2..)values(value1,value2...);insert into table_name set field1=value1,field2=value2...;(键 阅读全文