VSIZE(X)
【功能】返回X的大小(字节)数
【参数】x




select vsize(user),user from dual;
返回：6 asdied


　　select length('adfad合理') "bytesLengthIs" from dual --7

　　select lengthb('adfad') "bytesLengthIs" from dual --5

　　select lengthb('adfad合理') "bytesLengthIs" from dual --9

　　select vsize('adfad合理') "bytesLengthIs" from dual --9

　　select lengthc('adfad合理')"bytesLengthIs" from dual --7


　　lengthb=vsize

　　lengthc=length