增 insert
insert into 表名(字段名,)values(1,"zhangsan","123");
insert into 表名 )values(1,"zhangsan","123");
删 delete
delete from user_table
delete from user_table where user_name="tom" and user_sex="nan"
delete from user_table where user_name="tom" or user_sex="nan"
改 update
update 表名 set 字段=xx, where
查 select
select *from user_table where;
select user_name,user_sex from user_table;