演算子と関数(1)

SELECT  *
  FROM  CUSTOMER
 WHERE  GENDER = 'MAN';
 
/* <> : 같지 않음 */ 
SELECT  *
  FROM  CUSTOMER
 WHERE  GENDER <> 'MAN';

/* >= : ~보다 크거나 같음 */  
SELECT  *
  FROM  CUSTOMER
 WHERE  YEAR(JOIN_DATE) >= 2020;

/* <= : ~보다 작거나 같음 */  
SELECT  *
  FROM  CUSTOMER
 WHERE  YEAR(JOIN_DATE) <= 2019;
 
/* > : ~보다 큼 */  
SELECT  *
  FROM  CUSTOMER
 WHERE  YEAR(JOIN_DATE) > 2019;
 
/* < : ~보다 작음 */  
SELECT  *
  FROM  CUSTOMER
 WHERE  YEAR(JOIN_DATE) < 2020;
 

/* AND : 앞, 뒤 조건 모두 만족 */
SELECT  *
  FROM  CUSTOMER
 WHERE  GENDER = 'MAN'
   AND  ADDR = 'Gyeonggi';

/* NOT : 뒤에 오는 조건과 반대 */ 
SELECT  *
  FROM  CUSTOMER
 WHERE  NOT GENDER = 'MAN'
   AND  ADDR = 'Gyeonggi';

/* OR : 하나라도 만족 */    
SELECT  *
  FROM  CUSTOMER
 WHERE  GENDER = 'MAN'
    OR  ADDR = 'Gyeonggi';

/* BETWEEN a AND b : a와 b의 값 사이 */
SELECT  *
  FROM  CUSTOMER
 WHERE  YEAR(BIRTHDAY) BETWEEN 2010 AND 2011;

/* NOT BETWEEN a AND b : a와 b의 값 사이가 아님 */
SELECT  *
  FROM  CUSTOMER
 WHERE  YEAR(BIRTHDAY) NOT BETWEEN 1950 AND 2020;

/* IN (List) : 리스트 값 */ 
SELECT  *
  FROM  CUSTOMER
 WHERE  YEAR(BIRTHDAY) IN (2010,2011);
 
/* NOT IN (List) : 리스트 값이 아님 */  
SELECT  *
  FROM  CUSTOMER
 WHERE  YEAR(BIRTHDAY) NOT IN (2010, 2011);

/* LIKE ‘비교문자열’ */   
SELECT  *
  FROM  CUSTOMER
 WHERE  ADDR LIKE 'D%'; /* ~로 시작하는 */

SELECT  *
  FROM  CUSTOMER
 WHERE  ADDR LIKE '%N'; /* ~로 끝나는 */
 
SELECT  *
  FROM  CUSTOMER
 WHERE  ADDR LIKE '%EO%'; /* ~를 포함하는 */

/* NOT LIKE ‘비교문자열’ */   
SELECT  *
  FROM  CUSTOMER
 WHERE  ADDR NOT LIKE '%EO%'; /* ~를 제외하는 */ 
 
/* IS NULL : NULL */   
SELECT  *
  FROM  CUSTOMER AS A
  LEFT
  JOIN  SALES AS B
    ON  A.MEM_NO = B.MEM_NO
 WHERE  B.MEM_NO IS NULL;
 
/* 확인 */ 
SELECT  *
  FROM  SALES
 WHERE  MEM_NO = '1001736';
 
/* IS NOT NULL : NOT NULL */   
SELECT  *
  FROM  CUSTOMER AS A
  LEFT
  JOIN  SALES AS B
    ON  A.MEM_NO = B.MEM_NO
 WHERE  B.MEM_NO IS NOT NULL;
 

/***************산술 연산자***************/
  
SELECT  *
		,A.SALES_QTY * PRICE AS 결제금액
  FROM  SALES AS A
  LEFT
  JOIN  PRODUCT AS B
    ON  A.PRODUCT_CODE = B.PRODUCT_CODE;

 /***************집합 연산자***************/
 
CREATE TEMPORARY TABLE SALES_2019
SELECT  *
  FROM  SALES
 WHERE  YEAR(ORDER_DATE) = '2019';
 
/* 1235행 */
SELECT  *
  FROM  SALES_2019;

/* 3115행 */
SELECT  *
  FROM  SALES;

/* UNION : 2개 이상 테이블 중복된 행 제거 하여 집합(* 열 개수와 데이터 타입 일치) */
SELECT  *
  FROM  SALES_2019
UNION
SELECT  *
  FROM  SALES;

/* UNION ALL: 2개 이상 테이블 중복된 행 제거 없이 집합(* 열 개수와 데이터 타입 일치) */
SELECT 3115 + 1235;

SELECT  *
  FROM  SALES_2019
UNION ALL
SELECT  *
  FROM  SALES;