使用哪个SELECT语句从系统日期中提取年份并以“1998”格式显示？( )
SELECT TO_CHAR(SYSDATE,'yyyy') FROM dual;
SELECT TO_DATE(SYSDATE,'yyyy') FROM dual;
SELECT DECODE(SUBSTR(SYSDATE, 8), 'YYYY') FROM dual;
SELECT DECODE(SUBSTR(SYSDATE, 8), 'year') FROM dual;
SELECT TO_CHAR(SUBSTR(SYSDATE, 8,2),'yyyy') FROM dual;
