----------------

.91294525242582598

32.sqrt

返回数字n的

sql>selectsqrt(64),sqrt(10)fromdual;

sqrt(64)sqrt(10)

------------------

83.1622777

33.tan

返回数字的正切值

sql>selecttan(20),tan(10)fromdual;

tan(20)tan(10)

------------------

2.2371609.64836083

34.tanh

返回数字n的双曲正切值

sql>selecttanh(20),tan(20)fromdual;

tanh(20)tan(20)

------------------

12.2371609

35.trunc

照指定的度截取一个数

sql>selecttrunc(124.1666,-2)trunc1,trunc(124.16666,2)fromdual;

trunc1trunc(124.16666,2)

---------------------------

100124.16

36.add_months

增加或减去月份

sql>selectto_char(add_months(to_date(‘199912‘,‘yyyymm‘),2),‘yyyymm‘)fromdual;

to_cha

------

200002

sql>selectto_char(add_months(to_date(‘199912‘,‘yyyymm‘),-2),‘yyyymm‘)fromdual;

to_cha

------

199910

37st_day

返回日期的最后一天

sql>selectto_char(sysdate,‘yyyy.mm.dd‘),to_char((sysdate) 1,‘yyyy.mm.dd‘)fromdual;

to_char(syto_char((s

--------------------

2004.05.092004.05.10

sql>selecst_day(sysdate)fromdual;

st_day(s

----------

31-5月-04

38.months_between(date2,date1)

给date2-date1的月份

sql>selectmonths_between(‘19-12月-1999‘,‘19-3月-1999‘)mon_betweenfromdual;

mon_between

-----------

9

sql>selectmonths_between(to_date(‘2000.05.20‘,‘yyyy.mm.dd‘),to_date(‘2005.05.20‘,‘yyyy.mm.dd‘))mon_betwfromdual;

mon_betw

---------

-60

39.new_time(date,‘this‘,‘that‘)

给在this时区=other时区的日期和时间

sql>selectto_char(sysdate,‘yyyy.mm.ddhh24:mi:ss‘)bj_time,to_char(new_time