CREATE OR REPLACE FUNCTION Is_Number (
str_ VARCHAR2 ) RETURN VARCHAR2
IS
num_ NUMBER;
BEGIN
num_ := to_number(str_);
RETURN 'Y';
EXCEPTION
WHEN OTHERS THEN
RETURN 'N';
END Is_Number;
/函数
SQL> select Is_Number('12345') from dual;
IS_NUMBER('12345')
--------------------------------------------------------------------------------
Y
SQL> select Is_Number('123.45') from dual;
IS_NUMBER('123.45')
--------------------------------------------------------------------------------
Y
SQL> select Is_Number('123a') from dual;
IS_NUMBER('123A')
--------------------------------------------------------------------------------
N
SQL>select
方法二:经过 translate函数来实现方法
SELECT nvl2(translate('123','/1234567890','/'),'CHAR','NUMBER')
FROM dual ;异常
SQL> SELECT nvl2(translate('123','/1234567890','/'),'CHAR','NUMBER')
2 FROM dual;
NVL2(TRANSLATE('123','/1234567
------------------------------
NUMBER
SQL>
SQL> SELECT nvl2(translate('123A','/1234567890','/'),'CHAR','NUMBER')
2 FROM dual;
NVL2(TRANSLATE('123A','/123456
------------------------------
CHAR
SQL>co
在实际使用过程当中,能够根据状况选用这两种方法。第一种方法的好处是能够判断带小数的数字,而第二种方法只能判断整数。由于若是 translate 函数若是写成 translate('123A','/1234567890.','/') 这种形式是会有问题的。数字
SQL> select Is_Number('123.45.6') from dual; IS_NUMBER('123.45.6')--------------------------------------------------------------------------------N SQL> SQL> SELECT nvl2(translate('1234.5.6','/1234567890.','/'),'CHAR','NUMBER') 2 FROM dual; NVL2(TRANSLATE('1234.5.6','/12------------------------------NUMBER SQL>