20.COS
返回一个给定数字的余弦
SQL> select cos(-3.1415927) from dual; COS(-3.1415927) --------------- -1
21.COSH
返回一个数字反余弦值
SQL> select cosh(20) from dual; COSH(20) --------- 242582598
22.EXP
返回一个数字e的n次方根
SQL> select exp(2),exp(1) from dual; EXP(2) EXP(1) --------- --------- 7.3890561 2.7182818
23.FLOOR
对给定的数字取整数
SQL> select floor(2345.67) from dual; FLOOR(2345.67) -------------- 2345
24.LN
返回一个数字的对数值
SQL> select ln(1),ln(2),ln(2.7182818) from dual; LN(1) LN(2) LN(2.7182818) --------- --------- -------------
0 .69314718 .99999999
25.LOG(n1,n2)
返回一个以n1为底n2的对数
SQL> select log(2,1),log(2,4) from dual; LOG(2,1) LOG(2,4) --------- --------- 0 2
26.MOD(n1,n2)
返回一个n1除以n2的余数
SQL> select mod(10,3),mod(3,3),mod(2,3) from dual; MOD(10,3) MOD(3,3) MOD(2,3) --------- --------- ---------
1 0 2
27.POWER 返回n1的n2次方根
SQL> select power(2,10),power(3,3) from dual; POWER(2,10) POWER(3,3) ----------- ---------- 1024 27
28.ROUND和TRUNC 按照指定的精度进行舍入
SQL> select round(55.5),round(-55.4),trunc(55.5),trunc(-55.5) from dual; ROUND(55.5) ROUND(-55.4) TRUNC(55.5) TRUNC(-55.5)
----------- ------------ ----------- ------------
56 -55 55 -55
29.SIGN
取数字n的符号,大于0返回1,小于0返回-1,等于0返回0 SQL> select sign(123),sign(-100),sign(0) from dual; SIGN(123) SIGN(-100) SIGN(0) --------- ---------- ---------
1 -1 0
30.SIN
返回一个数字的正弦值
SQL> select sin(1.57079) from dual; SIN(1.57079) ------------ 1
31.SIGH
返回双曲正弦的值
SQL> select sin(20),sinh(20) from dual; SIN(20) SINH(20) --------- --------- .91294525 242582598
32.SQRT 返回数字n的根
SQL> select sqrt(64),sqrt(10) from dual; SQRT(64) SQRT(10) --------- --------- 8 3.1622777
33.TAN
返回数字的正切值
SQL> select tan(20),tan(10) from dual; TAN(20) TAN(10) --------- --------- 2.2371609 .64836083
34.TANH
返回数字n的双曲正切值
SQL> select tanh(20),tan(20) from dual; TANH(20) TAN(20) --------- --------- 1 2.2371609
35.TRUNC
按照指定的精度截取一个数
SQL> select trunc(124.1666,-2) trunc1,trunc(124.16666,2) from dual; TRUNC1 TRUNC(124.16666,2) --------- ------------------
100 124.16
36.ADD_MONTHS 增加或减去月份
SQL> select to_char(add_months(to_date('199912','yyyymm'),2),'yyyymm') from dual; TO_CHA ------ 200002
SQL> select to_char(add_months(to_date('199912','yyyymm'),-2),'yyyymm') from dual; TO_CHA ------ 199910
37.LAST_DAY 返回日期的最后一天
SQL> select to_char(sysdate,'yyyy.mm.dd'),to_char((sysdate)+1,'yyyy.mm.dd') from dual; TO_CHAR(SY TO_CHAR((S ---------- ---------- 2004.05.09 2004.05.10
SQL> select last_day(sysdate) from dual; LAST_DAY(S ---------- 31-5月 -04
38.MONTHS_BETWEEN(date2,date1) 给出date2-date1的月份
SQL> select months_between('19-12月-1999','19-3月-1999') mon_between from dual; MON_BETWEEN ----------- 9
SQL>selectmonths_between(to_date('2000.05.20','yyyy.mm.dd'),to_date('2005.05.20','yyyy.mm.dd')) mon_betw from dual; MON_BETW --------- -60
39.NEW_TIME(date,'this','that')
给出在this时区=other时区的日期和时间
SQL> select to_char(sysdate,'yyyy.mm.dd hh24:mi:ss') bj_time,to_char(new_time 2 (sysdate,'PDT','GMT'),'yyyy.mm.dd hh24:mi:ss') los_angles from dual; BJ_TIME LOS_ANGLES ------------------- -------------------