DB_날짜형식 변환하기

DATE_FORMAT(변환시킬값, '변환하고싶은날짜형식의 양식') 

* 대소문자 예민

 

MYSQL VER.

 

 

select DATE_FORMAT(consulting_date,'%Y-%m') as yearMonth, count(consulting_date) as studentCount from consulting 
	join student on student_id=student_consulting_id
		where consulting_deletion="N" and teacher_student_id="49"
		and consulting_date like "2021%"
			group by DATE_FORMAT(consulting_date,'%Y-%m')
            	order by yearMonth asc;

 

MAPPER VER.

**mapper에 넣을때  like concat(#{thisYear},"%") 

-concat으로 이어붙여쓰기!!!!!!

<select id="getPerConsultingInfo" resultType="kr.portfolio.forfree.vo.DataVO">
	select DATE_FORMAT(consulting_date,"%Y-%m") as yearMonth, count(consulting_date) as studentCount from consulting 
		join student on student_id=student_consulting_id
			where consulting_deletion="N" and teacher_student_id=#{teacher_id} and consulting_date like concat(#{thisYear},"%")
				group by DATE_FORMAT(consulting_date,"%Y-%m")
					order by yearMonth asc;
</select>

참고블로그: https://kig6022.tistory.com/7