oracle取值函数
oracle取值函数
1.绝对值:abs() select abs(-2) value from dual; 2.取整函数(大):ceil() select ceil(-2.001) value from dual;(-2) 3.取整函数(小):floor() select floor(-2.001) value from dual;(-3) 4.取整函数(截取):trunc() select trunc(-2.001) value from dual; (-2) 5.四舍五入:round() select round(1.234564) value from dual;(1.2346) 6.取平方:Power(m,n) select power(4,2) value from dual;(16) 7.取平方根:SQRT() select sqrt(16) value from dual;(4) 8.取随机数:dbms_random(minvalue,maxvalue) select sys.dbms.random.value(0,1) value from dual; 9.取符号:Sign() select sign(-3) value from dual;(-) 10,取集合的最大值:greatest(value) select greatest(-1,3,5,7,9) value from dual;(9) 11.取集合的最小值:least(value) select least(-1,3,5,7,9) value from dual;(-1) 12.处理Null值:nvl(空值,代替值) select nvl(null,10) value from dual;(10) 13.求字符序号:ascii() select ascii(a) value from dual; 14.求序号字符:chr() select chr(97) value from dual; 15.链接:concat() select concat("11","22") value from dual;(1122) 16.获取系统时间:sysdate() select sysdate value from dual; 17.求日期 select trunc(sysdate) from dual; 18.求时间 select to_char(sysdate,"hh24:mm:ss") from dual; 19.首字母大写:InitCAP() select INITCAP(abc def ghi) value from dual;(Abc Def Ghi)