]]>oracle道消息http://www.aygfsteel.com/zhpeng/archive/2007/05/29/120594.html?j)随我?/dc:creator>?j)随我?/author>Tue, 29 May 2007 01:16:00 GMThttp://www.aygfsteel.com/zhpeng/archive/2007/05/29/120594.htmlhttp://www.aygfsteel.com/zhpeng/comments/120594.htmlhttp://www.aygfsteel.com/zhpeng/archive/2007/05/29/120594.html#Feedback0http://www.aygfsteel.com/zhpeng/comments/commentRss/120594.htmlhttp://www.aygfsteel.com/zhpeng/services/trackbacks/120594.html1?oracle是态度鲜明的站在linux一边的,如果你听qoracle老ȝ演讲,你就?x)知?他把比尔盖茨批的一文不?从oralce的广告词oracle make linus unbreakable,也可以证明我所说的?世界不会(x)是单调的,linuxl会(x)有好的发?请大家相信这一?
2 、orcle以后全面兼容java的源代码,而从ORACLE DB 9.2.0.2开?ORACLE开始用JAVA开发升U?ORACLE所有的产品.q是切消息.
]]>MS SQL server和Oracle的函数对?/title>http://www.aygfsteel.com/zhpeng/archive/2006/08/14/63531.html?j)随我?/dc:creator>?j)随我?/author>Mon, 14 Aug 2006 13:06:00 GMThttp://www.aygfsteel.com/zhpeng/archive/2006/08/14/63531.htmlhttp://www.aygfsteel.com/zhpeng/comments/63531.htmlhttp://www.aygfsteel.com/zhpeng/archive/2006/08/14/63531.html#Feedback0http://www.aygfsteel.com/zhpeng/comments/commentRss/63531.htmlhttp://www.aygfsteel.com/zhpeng/services/trackbacks/63531.html 1.l对? S:select abs(-1) value O:select abs(-1) value from dual 2.取整(? S:select ceiling(-1.001) value O:select ceil(-1.001) value from dual 3.取整Q小Q? S:select floor(-1.001) value O:select floor(-1.001) value from dual 4.取整Q截取)(j) S:select cast(-1.002 as int) value O:select trunc(-1.002) value from dual 5.四舍五入 S:select round(1.23456,4) value 1.23460 O:select round(1.23456,4) value from dual 1.2346 6.e为底的幂 S:select Exp(1) value 2.7182818284590451 O:select Exp(1) value from dual 2.71828182 7.取e为底的对?br /> S:select log(2.7182818284590451) value 1 O:select ln(2.7182818284590451) value from dual; 1 8.?0为底Ҏ(gu) S:select log10(10) value 1 O:select log(10,10) value from dual; 1 9.取^?br /> S:select SQUARE(4) value 16 O:select power(4,2) value from dual 16 10.取^Ҏ(gu) S:select SQRT(4) value 2 O:select SQRT(4) value from dual 2 11.求Q意数为底的幂 S:select power(3,4) value 81 O:select power(3,4) value from dual 81 12.取随机数 S:select rand() value O:select sys.dbms_random.value(0,1) value from dual; 13.取符?br /> S:select sign(-8) value -1 O:select sign(-8) value from dual -1 ----------数学函数 14.圆周?br /> S:SELECT PI() value 3.1415926535897931 O:不知?br /> 15.sin,cos,tan 参数都以弧度为单?br /> 例如Qselect sin(PI()/2) value 得到1QSQLServerQ?br /> 16.Asin,Acos,Atan,Atan2 q回弧度 17.弧度角度互换(SQLServerQOracle不知? DEGREESQ弧?〉角?br /> RADIANSQ角?〉弧?br /> ---------数值间比较 18. 求集合最大?br /> S:select max(value) value from (select 1 value union select -2 value union select 4 value union select 3 value)a O:select greatest(1,-2,4,3) value from dual 19. 求集合最?br /> S:select min(value) value from (select 1 value union select -2 value union select 4 value union select 3 value)a O:select least(1,-2,4,3) value from dual 20.如何处理null?F2中的null?0代替) S:select F1,IsNull(F2,10) value from Tbl O:select F1,nvl(F2,10) value from Tbl --------数值间比较 21.求字W序?br /> S:select ascii('a') value O:select ascii('a') value from dual 22.从序h字符 S:select char(97) value O:select chr(97) value from dual 23.q接 S:select '11'+'22'+'33' value O:select CONCAT('11','22')||33 value from dual 23.子串位置 --q回3 S:select CHARINDEX('s','sdsq',2) value O:select INSTR('sdsq','s',2) value from dual 23.模糊子串的位|?--q回2,参数L中间%则返? S:select patindex('%d%q%','sdsfasdqe') value O:oracle没发玎ͼ但是instr可以通过W四N刂瞥鱿执问?BR> select INSTR('sdsfasdqe','sd',1,2) value from dual q回6 24.求子?br /> S:select substring('abcd',2,2) value O:select substr('abcd',2,2) value from dual 25.子串代替 q回aijklmnef S:SELECT STUFF('abcdef', 2, 3, 'ijklmn') value O:SELECT Replace('abcdef', 'bcd', 'ijklmn') value from dual 26.子串全部替换 S:没发?br /> O:select Translate('fasdbfasegas','fa','? ) value from dual 27.长度 S:len,datalength O:length 28.大小写{?lower,upper 29.单词首字母大?br /> S:没发?br /> O:select INITCAP('abcd dsaf df') value from dual 30.左补I格QLPAD的第一个参Cؓ(f)I格则同space函数Q?br /> S:select space(10)+'abcd' value O:select LPAD('abcd',14) value from dual 31.双I格QRPAD的第一个参Cؓ(f)I格则同space函数Q?br /> S:select 'abcd'+space(10) value O:select RPAD('abcd',14) value from dual 32.删除I格 S:ltrim,rtrim O:ltrim,rtrim,trim 33. 重复字符?br /> S:select REPLICATE('abcd',2) value O:没发?br /> 34.发音怼性比?q两个单词返回gP发音相同) S:SELECT SOUNDEX ('Smith'), SOUNDEX ('Smythe') O:SELECT SOUNDEX ('Smith'), SOUNDEX ('Smythe') from dual SQLServer中用SELECT DIFFERENCE('Smithers', 'Smythers') 比较soundex的差 q回0-4Q?为同韻I1最?br /> --------------日期函数 35.pȝ旉 S:select getdate() value O:select sysdate value from dual 36.前后几日 直接与整数相加减 37.求日?br /> S:select convert(char(10),getdate(),20) value O:select trunc(sysdate) value from dual select to_char(sysdate,'yyyy-mm-dd') value from dual 38.求时?br /> S:select convert(char(8),getdate(),108) value O:select to_char(sysdate,'hh24:mm:ss') value from dual 39.取日期时间的其他部分 S:DATEPART ?DATENAME 函数Q第一个参数决定)(j) O:to_char函数 W二个参数决?br /> 参数---------------------------------下表需要补?br /> year yy, yyyy quarter qq, q (季度) month mm, m (m O无效) dayofyear dy, y (O表星? day dd, d (d O无效) week wk, ww (wk O无效) weekday dw (O不清? Hour hh,hh12,hh24 (hh12,hh24 S无效) minute mi, n (n O无效) second ss, s (s O无效) millisecond ms (O无效) ---------------------------------------------- 40.当月最后一?br /> S:不知?br /> O:select LAST_DAY(sysdate) value from dual 41.本星期的某一天(比如星期日)(j) S:不知?br /> O:SELECT Next_day(sysdate,7) vaule FROM DUAL; 42.字符串{旉 S:可以直接转或者select cast('2004-09-08'as datetime) value O:SELECT To_date('2004-01-05 22:09:38','yyyy-mm-dd hh24-mi-ss') vaule FROM DUAL; 43.求两日期某一部分的差Q比如秒Q?br /> S:select datediff(ss,getdate(),getdate()+12.3) value O:直接用两个日期相减(比如d1-d2=12.3Q?br /> SELECT (d1-d2)*24*60*60 vaule FROM DUAL; 44.Ҏ(gu)差值求新的日期Q比如分钟)(j) S:select dateadd(mi,8,getdate()) value O:SELECT sysdate+8/60/24 vaule FROM DUAL; 45.求不同时区时?br /> S:不知?br /> O:SELECT New_time(sysdate,'ydt','gmt' ) vaule FROM DUAL; -----时区参数,北京在东8区应该是Ydt------- AST ADT 大西z标准时?br /> BST BDT 白o(h)h准时?br /> CST CDT 中部标准旉 EST EDT 东部标准旉 GMT 格林治标准旉 HST HDT 阿拉斯加—夏威夷标准旉 MST MDT 山区标准旉 NST U芬兰标准时?br /> PST PDT 太^z标准时?br /> YST YDT YUKON标准旉