Oracleѧϰ±Ê¼Ç3

Ò»£®³£¼ûµ¥Ðк¯Êý(¶ÔÿÐмǼ½øÐвÙ×÷)
1£©lower(str)                                           //lower()ת»»ÎªÐ¡Ð´
2£©upper(str)                                           //upper()ת»»Îª´óд
3£©//´ÓstrÈ¡´ÓbeginλÖÿªÊ¼£¬ÊýĿΪnumµÄ×Ó×Ö·û´®
       //begin´Ó1¿ªÊ¼
substr(str, begin, num)
4£©chr(65)àA                                //½«Ò»¸öÊý×Öת»»ÎªasciiÏà¶ÔÓ¦µÄÖµ
5£©ascii(‘A’)à65                      //½«×Ö·ûתΪasciiÂë
6£©round(23.65)à24                       //ËÄÉáÎåÈë
              round(23.65, 1)à23.7
7£©//½«Êý×ÖÀàÐÍsalaryת»¯ÎªÌض¨¸ñʽÊä³ö
select to_char(salary, ‘$999,999.999’) from emp;
//½«date°´Ìض¨µÄ¸ñʽÊä³ö
Select to_char(date, ‘YYYY-MM-DD HH:MI:SS’) from emp;
8£©//½«×Ö·û´®×ª»¯Îªdate¸ñʽ
select * from emp
where indate >
to_date(‘1985-11-22 10:10:11’, ‘YYYY-MM-DD HH:MI:SS’);
9£©//½«×Ö·û´®×ªÎªnumber
              To_number(‘$1,250,00’, ‘$9,999,99’);
10£©