oracle单行函数之类型转换

 1 SQL> select to_char(sysdate, ‘yyyy-mm-dd day‘) from dual;
 2  
 3 TO_CHAR(SYSDATE,‘YYYY-MM-DDDAY
 4 ------------------------------
 5 2014-12-23 星期二
 6 
 7 SQL> select to_char(sysdate,‘"今天是"yyyy-dd-mm day ",大家好"‘) from dual;
 8  
 9 TO_CHAR(SYSDATE,‘"今天是"YYYY-
10 -------------------------------------------
11 今天是2014-23-12 星期二 ,大家好

 1 SQL> select sal,to_char(sal,‘L9,999.99‘) from emp;
 2  
 3       SAL TO_CHAR(SAL,‘L9,999.99‘)
 4 --------- ------------------------
 5    800.00           ￥800.00
 6   1600.00         ￥1,600.00
 7   1250.00         ￥1,250.00
 8   2975.00         ￥2,975.00
 9   1250.00         ￥1,250.00
10   2850.00         ￥2,850.00
11   2450.00         ￥2,450.00
12   5000.00         ￥5,000.00
13   1500.00         ￥1,500.00
14    950.00           ￥950.00
15   3000.00         ￥3,000.00
16   1400.00         ￥1,400.00
17   2000.00         ￥2,000.00
18  
19 13 rows selected