23.09.29. SQL Developer 알고리즘 문제 ③

3. 직각삼각형 출력

-- 예제113. 직각삼각형을 sql로 출력할 수 있을까?
select lpad(' ',  2, '★') -- lpad(공백, 전체 자릿수, 넣을 모양)
    from dual ;

with loop_table as ( select level as num
                                    from dual 
                                    connect by level <= 8 )
select lpad('★', num, '★') as star
    from loop_table ;
    
-- 문제1. 위의 삼각형을 뒤집어서 출력하세요.
with loop_table as ( select 9-level as num
                                    from dual 
                                    connect by level <= 8 )
select lpad('★', num, '★') as star
    from loop_table ;

-- 문제2. 마름모의 세로절반을 출력하세요.
with loop_table as ( select level as num
                                    from dual 
                                    connect by level <= 8 ) 
select lpad('★', num, '★') as star
    from loop_table 
union all
select lpad('★', 9-num, '★') as star
    from loop_table;