pl-sql它无法比较两个字符串？为什么

Question

declare 
    v_date varchar2(15); 
begin 
    v_date := to_char(sysdate, 'DAY'); 
    if upper(v_date) = to_char('TUESDAY') then 
    dbms_output.put_line('Today is Tuesday'); 
    else 
    dbms_output.put_line('Today is not tuesday'|| upper(v_date)); 
    end if ; 
end; 

Answer 1

请修修你从白天的TO_CHAR获得的价值，那么你应该得到正确的结果

declare 
    v_date varchar2(15); 
begin 
    v_date := to_char(sysdate, 'DAY'); 
    if trim(v_date) = 'TUESDAY' then 
    dbms_output.put_line('Today is Tuesday'); 
    else 
    dbms_output.put_line('Today is not tuesday '|| v_date); 
    end if ; 
end;