months_between()months_between()months_between()months_between()months_between()months_between()months_between()months_between()months_between()
2017-05-07
試驗出來了,只能書寫純數(shù)字的字符串才能默認(rèn)轉(zhuǎn)換成數(shù)字:
例如:select to_number('1000') from dual;
例如:select to_number('1000') from dual;
2017-04-26
字符轉(zhuǎn)換成數(shù)字的函數(shù):to_number(char[,fmt]) (fmt是轉(zhuǎn)換的格式,可以省略),是怎么實現(xiàn)的?
2017-04-26