oracle函數

4.轉換函數:

---to_char
select to_char(hiredate,'yyyy-mm-dd') from emp
select to_char (hiredate,'yyyy"年"mm"月"dd"日"') from emp

select sal, to_char (sal, 'l0,000,000.00') as saltest from emp

結果:

查詢入職時間在1982年以後的員工:
select ename,hiredate from emp where hiredate>to_date('1981-12-31','yyyy-mm-dd')

查詢工資大於2000的全部員工:
select ename,sal from emp where sal>to_number('¥2000','l9999');

5.通用函數: