mysql入门操作

'''
1.增
'''
INSERT INTO WORKER
(FIRST_NAME,LAST_NAME,AGE,SEX,INCOME)
VALUES ('liu','bei','60','m','20000'),
       ('cao','cao','58','m','15000'),
       ('sun','quan','40','m','13000');
'''
2.修改列
'''
#修改列
alter table worker
change
SEX gender char();

#新增一列
alter table worker
add force float;

'''
3.修改
'''
update worker
set income=income+2000
where first_name='liu'

'''
4.删
'''
delete
from worker
where income>20000

'''
5.查
'''
select first_name
from worker
where income>200