create database db1 charset utf8;
# 查看当前创建的数据库show create database db1;# 查看所有的数据库show databases;
alter database db1 charset gbk;
drop database db1;
use db1; #切换文件夹select database(); #查看当前所在文件夹
create table t1(id int,name char);
#查看当前的这张t1表show create table t1;# 查看所有的表show tables;# 查看表的详细信息desc t1;
# modify修改的意思alter table t1 modify name char(6);# 改变name为大写的NAMEalter table t1 change name NAMA char(7);
# 删除表drop table t1;
# 插入一条数据,规定id,name数据leileiinsert t1(id,name) values(1,"mjj01"),(2,"mjj02"),(3,"mjj03");
select id from db1.t1;select id,name from db1.t1;select * from db1.t1;
update db1.t1 set name=‘zhangsan‘;update db1.t1 set name=‘alex‘ where id=2;
delete from t1;delete from t1 where id=2;