집약
합쳐서 하나 CREATE TABLE PriceByAge (product_id VARCHAR(32) NOT NULL, low_age INTEGER NOT NULL, high_age INTEGER NOT NULL, price INTEGER NOT NULL, PRIMARY KEY (product_id, low_age), CHECK (low_age < high_age)); INSERT INTO PriceByAge VALUES('제품1', 0 , 50 , 2000); INSERT INTO PriceByAge VALUES('제품1', 51 , 100 , 3000); INSERT INTO PriceByAge VALUES('제품2', 0 , 100 , 4200); INSERT INTO PriceByAge VALUES(..
집계와 조건분기
집계 대상으로 조건 분기 -테이블 생성 CREATE TABLE Population( prefecture VARCHAR(32), sex CHAR(1), pop INTEGER, CONSTRAINT pk_pop PRIMARY KEY(prefecture, sex) ); -데이터 insert INSERT INTO Population VALUES('성남', '1', 60); INSERT INTO Population VALUES('성남', '2', 40); INSERT INTO Population VALUES('수원', '1', 90); INSERT INTO Population VALUES('수원', '2',100); INSERT INTO Population VALUES('광명', '1',100); INSERT IN..
