sql문 연습

CREATE TABLE 테이블명( 내용들)

INSERT INTO [테이블이름](칼럼명1, 칼럼명2, ..., [칼럼명n]

values([값1], [값2], ..., [값n]);

SELECT * (전체 혹은 행) FROM 테이블명

UPDATE 테이블명 SET 행이름 = 뭘로할건지

DELETE FROM 테이블명 WHERE 조건

db는 엑셀파일

테이블은 엑셀시트

create table test1 (

user_id VARCHARACTER (100)

, user_pass VARCHARACTER(100)

, user_name VARCHARACTER(100)

, user_age int(5)

);

INSERT INTO [테이블이름](칼럼명1, 칼럼명2, ..., [칼럼명n]

values([값1], [값2], ..., [값n]);

INSERT INTO test1 values('korea','123456','test',20);

INSERT INTO test1 values('korea1','aa123456','a',320);

INSERT INTO test1 values('korea2','ss123456','b',420);

INSERT INTO test1 values('korea3','dd123456','c',520);

INSERT INTO test1 values('korea4','cc123456','d',20);

INSERT INTO test1 values('korea5','123456','test',20);

INSERT INTO test1 values('korea6','123456','1test',20);

INSERT INTO test1 values('korea','123456','e',520);

INSERT INTO test1 values('korea','ff123456','f',20);

INSERT INTO test1 values('korea','ww123456','g',20);

select * from test1;

# user_id가 korea인 것을 조회해라;

select * from test1 where user_id='korea1';

select user_id from test1 where user_id='korea1';

update test1 set user_name='academy' where user_id=(select user_id from test1 where user_id='korea1');

delete from test1 where user_id='korea'; 

# user_name에 te가 들어간 아이를 검색해

delete from test1 where user_name like '%te%';

# %는 아무문자가 들어갈수 있다.

select 

user_id

, user_pass

, user_name

, avg(user_age)

from test1 

GROUP by user_id ;

select * from test1 order by user_id desc , user_age desc;