首先建立数据库连接：(x)
-- Drop existing database link
drop public database link DB4960;
-- Create database link
create public database link DB4960
connect to ctile identified by ctile
using '(DESCRIPTION =
(ADDRESS_LIST =
(ADDRESS = (PROTOCOL = TCP)(HOST = 172.11.41.60)(PORT = 1521))
)
(CONNECT_DATA =
(SERVICE_NAME = ORCL)
)
)';
然后需要徏立同义词Q?br /> create public synonym mistel.table for mistel.table@DB4960;
然后可以在本地使用select * from mistel.table 查询DB4960上的数据库表?
]]>
SCNQ系l改变号Q，它的英文全拼为：(x)System Change Number Q它是数据库中非帔R要的一个数据结构?br /> SCN提供?jin)Oracle的内部时钟机Ӟ可被看作逻辑旉Q这对于恢复操作是至关重要的
注释QOracle 仅根?SCN 执行恢复?br /> 它定义了(jin)数据库在某个切时刻提交的版本。在事物提交Ӟ它被赋予一个唯一的标CZ物的SCN 。一些h认ؓ(f) SCN 是指Q?System Commit Number Q而通常 SCN 在提交时才变化，所以很多情况下Q?br /> q两个名词经常被交替使用?br /> I竟是哪个词其实Ҏ(gu)们来说ƈ不是最重要的，重要的是我们知道 SCN ?Oracle 内部的时钟机Ӟ Oracle 通过 SCN 来维护数据库的一致性，q过SCN 实施 Oracle 臛_重要的恢复机制?br /> 具体执行程我们可从以下几个CZ图中体会(x);
1.原表记录 $ sqlplus eygle/eygle
SQL*Plus: Release 10.1.0.2.0 - Production on Wed Mar 30 08:52:04 2005
Copyright (c) 1982, 2004, Oracle. All rights reserved.
Connected to:
Oracle Database 10g Enterprise Edition Release 10.1.0.2.0 - 64bit Production
With the Partitioning, OLAP and Data Mining options
SQL>select count(*) from t1;
COUNT(*)
----------
9318
2.误删除所有记?br /> q且提交更改?br /> SQL>delete from t1;
9318 rows deleted.
SQL>commit;
Commit complete.
SQL>select count(*) from t1;
COUNT(*)
----------
0
3.获得当前SCN
如果能够切知道删除之前SCN最好，如果不知道，可以q行闪回查询试.
SQL>select dbms_flashback.get_system_change_number from dual;
GET_SYSTEM_CHANGE_NUMBER
------------------------
10671006
SQL>select count(*) from t1 as of scn 10671000;
COUNT(*)
----------
0
SQL>select count(*) from t1 as of scn 10670000;
COUNT(*)
----------
9318
我们看到在SCN=10670000Ӟ数据都在?br /> 4.恢复数据.
SQL>insert into t1 select * from t1 as of scn 10670000;
9318 rows created.
SQL>commit;
Commit complete.
SQL>select count(*) from t1;
COUNT(*)
----------
9318
文章2
误删数据后的q原
select timestamp_to_scn(to_timestamp('2009-03-13 09:00:00','YYYY-MM-DD HH:MI:SS')) from dual;
l果:13526973
删除时间{换ؓ(f)scn
select * from reportinfo
AS OF SCN 13526973
reportinfo表中的scn点的数据取出
然后可以Ҏ(gu)q个数据q行q原操作
create table reporttest as select * from reportinfo where 1=0;
insert into reporttest select * from reportinfo AS OF SCN 13526973;
--上面两句应该可以合成一?br /> --create table reporttest as select * from reportinfo AS OF SCN 13526973;
q是reporttest表中是scn点的reportinfo数据.处理卛_
]]>
一、基
1、说明：(x)创徏数据?/p>
CREATE DATABASE database-name
2、说明：(x)删除数据?/p>
drop database dbname
3、说明：(x)备䆾sql server
--- 创徏 备䆾数据?device
USE master
EXEC sp_addumpdevice 'disk', 'testBack', 'c:\mssql7backup\MyNwind_1.dat'
--- 开?备䆾
BACKUP DATABASE pubs TO testBack
4、说明：(x)创徏新表
create table tabname(col1 type1 [not null] [primary key],col2 type2 [not null],..)
Ҏ(gu)已有的表创徏新表Q?
AQcreate table tab_new like tab_old (使用旧表创徏新表)
BQcreate table tab_new as select col1,col2... from tab_old definition only
5、说明：(x)删除新表
drop table tabname
6、说明：(x)增加一个列
Alter table tabname add column col type
注：(x)列增加后不能删除。DB2中列加上后数据类型也不能改变Q唯一能改变的是增加varcharcd的长度?/p>
7、说明：(x)d主键Q?Alter table tabname add primary key(col)
说明Q删除主键：(x) Alter table tabname drop primary key(col)
8、说明：(x)创徏索引Qcreate [unique] index idxname on tabname(col....)
删除索引Qdrop index idxname
注：(x)索引是不可更改的Q想更改必须删除重新建?/p>
9、说明：(x)创徏视图Qcreate view viewname as select statement
删除视图Qdrop view viewname
10、说明：(x)几个单的基本的sql语句
选择Qselect * from table1 where 范围
插入Qinsert into table1(field1,field2) values(value1,value2)
删除Qdelete from table1 where 范围
更新Qupdate table1 set field1=value1 where 范围
查找Qselect * from table1 where field1 like '%value1%' ---like的语法很_֦Q查资料!
排序Qselect * from table1 order by field1,field2 [desc]
LQselect count as totalcount from table1
求和Qselect sum(field1) as sumvalue from table1
q_Qselect avg(field1) as avgvalue from table1
最大：(x)select max(field1) as maxvalue from table1
最：(x)select min(field1) as minvalue from table1
11、说明：(x)几个高查询q算?/p>
AQ?UNION q算W?
UNION q算W通过l合其他两个l果表（例如 TABLE1 ?TABLE2Qƈ消去表中M重复行而派生出一个结果表。当 ALL ?UNION 一起用时Q即 UNION ALLQ，不消除重复行。两U情况下Q派生表的每一行不是来?TABLE1 是来自 TABLE2?
BQ?EXCEPT q算W?
EXCEPT q算W通过包括所有在 TABLE1 中但不在 TABLE2 中的行ƈ消除所有重复行而派生出一个结果表。当 ALL ?EXCEPT 一起用时 (EXCEPT ALL)Q不消除重复行?
CQ?INTERSECT q算W?/p>
INTERSECT q算W通过只包?TABLE1 ?TABLE2 中都有的行ƈ消除所有重复行而派生出一个结果表。当 ALL ?INTERSECT 一起用时 (INTERSECT ALL)Q不消除重复行?
注：(x)使用q算词的几个查询l果行必L一致的?
12、说明：(x)使用外连?
A、left outer joinQ?
左外q接Q左q接Q：(x)l果集几包括q接表的匚w行，也包括左q接表的所有行?
SQL: select a.a, a.b, a.c, b.c, b.d, b.f from a LEFT OUT JOIN b ON a.a = b.c
BQright outer join:
叛_q接(双?Q结果集既包括连接表的匹配连接行Q也包括双接表的所有行?
CQfull outer joinQ?
全外q接Q不仅包括符可接表的匹配行Q还包括两个q接表中的所有记录?/p>
二、提?/p>
1、说明：(x)复制?只复制结?源表名：(x)a 新表名：(x)b) (Access可用)
法一Qselect * into b from a where 1<>1
法二Qselect top 0 * into b from a
2、说明：(x)拯?拯数据,源表名：(x)a 目标表名Qb) (Access可用)
insert into b(a, b, c) select d,e,f from b;
3、说明：(x)跨数据库之间表的拯(具体数据使用l对路径) (Access可用)
insert into b(a, b, c) select d,e,f from b in '具体数据? where 条g
例子Q?.from b in '"&Server.MapPath(".")&"\data.mdb" &"' where..
4、说明：(x)子查?表名1Qa 表名2Qb)
select a,b,c from a where a IN (select d from b ) 或? select a,b,c from a where a IN (1,2,3)
5、说明：(x)昄文章、提交h和最后回复时?/p>
select a.title,a.username,b.adddate from table a,(select max(adddate) adddate from table where table.title=a.title) b
6、说明：(x)外连接查?表名1Qa 表名2Qb)
select a.a, a.b, a.c, b.c, b.d, b.f from a LEFT OUT JOIN b ON a.a = b.c
7、说明：(x)在线视图查询(表名1Qa )
select * from (SELECT a,b,c FROM a) T where t.a > 1;
8、说明：(x)between的用?between限制查询数据范围时包括了(jin)边界?not between不包?/p>
select * from table1 where time between time1 and time2
select a,b,c, from table1 where a not between 数? and 数?
9、说明：(x)in 的用方?/p>
select * from table1 where a [not] in ('?','?','?','?')
10、说明：(x)两张兌表，删除主表中已l在副表中没有的信息
delete from table1 where not exists ( select * from table2 where table1.field1=table2.field1 )
11、说明：(x)四表联查问题Q?/p>
select * from a left inner join b on a.a=b.b right inner join c on a.a=c.c inner join d on a.a=d.d where .....
12、说明：(x)日程安排提前五分钟提?
SQL: select * from 日程安排 where datediff('minute',f开始时?getdate())>5
13、说明：(x)一条sql 语句搞定数据库分?/p>
select top 10 b.* from (select top 20 主键字段,排序字段 from 表名 order by 排序字段 desc) a,表名 b where b.主键字段 = a.主键字段 order by a.排序字段
14、说明：(x)?0条记?/p>
select top 10 * form table1 where 范围
15、说明：(x)选择在每一lb值相同的数据中对应的a最大的记录的所有信?cMq样的用法可以用于论坛每月排行榜,每月热销产品分析,按科目成l排?{等.)
select a,b,c from tablename ta where a=(select max(a) from tablename tb where tb.b=ta.b)
16、说明：(x)包括所有在 TableA 中但不在 TableB和TableC 中的行ƈ消除所有重复行而派生出一个结果表
(select a from tableA ) except (select a from tableB) except (select a from tableC)
17、说明：(x)随机取出10条数?/p>
select top 10 * from tablename order by newid()
18、说明：(x)随机选择记录
select newid()
19、说明：(x)删除重复记录
Delete from tablename where id not in (select max(id) from tablename group by col1,col2,...)
20、说明：(x)列出数据库里所有的表名
select name from sysobjects where type='U'
21、说明：(x)列出表里的所有的
select name from syscolumns where id=object_id('TableName')
22、说明：(x)列示type、vender、pcs字段Q以type字段排列Qcase可以方便地实现多重选择Q类似select 中的case?/p>
select type,sum(case vender when 'A' then pcs else 0 end),sum(case vender when 'C' then pcs else 0 end),sum(case vender when 'B' then pcs else 0 end) FROM tablename group by type
昄l果Q?/p>
type vender pcs
?sh)?A 1
?sh)?A 1
光盘 B 2
光盘 A 2
手机 B 3
手机 C 3
23、说明：(x)初始化表table1
TRUNCATE TABLE table1
24、说明：(x)选择?0?5的记?/p>
select top 5 * from (select top 15 * from table order by id asc) table_别名 order by id desc
三、技?/p>
1?=1Q?=2的用，在SQL语句l合时用的较?/p>
"where 1=1" 是表C选择全部 "where 1=2"全部不选，
如：(x)
if @strWhere !=''
begin
set @strSQL = 'select count(*) as Total from [' + @tblName + '] where ' + @strWhere
end
else
begin
set @strSQL = 'select count(*) as Total from [' + @tblName + ']'
end
我们可以直接写成
set @strSQL = 'select count(*) as Total from [' + @tblName + '] where 1=1 安定 '+ @strWhere
2、收~数据库
--重徏索引
DBCC REINDEX
DBCC INDEXDEFRAG
--收羃数据和日?/p>
DBCC SHRINKDB
DBCC SHRINKFILE
3、压~数据库
dbcc shrinkdatabase(dbname)
4、{UL据库l新用户以已存在用户权限
exec sp_change_users_login 'update_one','newname','oldname'
go
5、检查备份集
RESTORE VERIFYONLY from disk='E:\dvbbs.bak'
6、修复数据库
ALTER DATABASE [dvbbs] SET SINGLE_USER
GO
DBCC CHECKDB('dvbbs',repair_allow_data_loss) WITH TABLOCK
GO
ALTER DATABASE [dvbbs] SET MULTI_USER
GO
7、日志清?/p>
SET NOCOUNT ON
DECLARE @LogicalFileName sysname,
@MaxMinutes INT,
@NewSize INT
USE tablename -- 要操作的数据库名
SELECT @LogicalFileName = 'tablename_log', -- 日志文g?/p>
@MaxMinutes = 10, -- Limit on time allowed to wrap log.
@NewSize = 1 -- 你想讑֮的日志文件的大小(M)
-- Setup / initialize
DECLARE @OriginalSize int
SELECT @OriginalSize = size
FROM sysfiles
WHERE name = @LogicalFileName
SELECT 'Original Size of ' + db_name() + ' LOG is ' +
CONVERT(VARCHAR(30),@OriginalSize) + ' 8K pages or ' +
CONVERT(VARCHAR(30),(@OriginalSize*8/1024)) + 'MB'
FROM sysfiles
WHERE name = @LogicalFileName
CREATE TABLE DummyTrans
(DummyColumn char (8000) not null)
DECLARE @Counter INT,
@StartTime DATETIME,
@TruncLog VARCHAR(255)
SELECT @StartTime = GETDATE(),
@TruncLog = 'BACKUP LOG ' + db_name() + ' WITH TRUNCATE_ONLY'
DBCC SHRINKFILE (@LogicalFileName, @NewSize)
EXEC (@TruncLog)
-- Wrap the log if necessary.
WHILE @MaxMinutes > DATEDIFF (mi, @StartTime, GETDATE()) -- time has not expired
AND @OriginalSize = (SELECT size FROM sysfiles WHERE name = @LogicalFileName)
AND (@OriginalSize * 8 /1024) > @NewSize
BEGIN -- Outer loop.
SELECT @Counter = 0
WHILE ((@Counter < @OriginalSize / 16) AND (@Counter < 50000))
BEGIN -- update
INSERT DummyTrans VALUES ('Fill Log')
DELETE DummyTrans
SELECT @Counter = @Counter + 1
END
EXEC (@TruncLog)
END
SELECT 'Final Size of ' + db_name() + ' LOG is ' +
CONVERT(VARCHAR(30),size) + ' 8K pages or ' +
CONVERT(VARCHAR(30),(size*8/1024)) + 'MB'
FROM sysfiles
WHERE name = @LogicalFileName
DROP TABLE DummyTrans
SET NOCOUNT OFF
8、说明：(x)更改某个?/p>
exec sp_changeobjectowner 'tablename','dbo'
9、存储更改全部表
CREATE PROCEDURE dbo.User_ChangeObjectOwnerBatch
@OldOwner as NVARCHAR(128),
@NewOwner as NVARCHAR(128)
AS
DECLARE @Name as NVARCHAR(128)
DECLARE @Owner as NVARCHAR(128)
DECLARE @OwnerName as NVARCHAR(128)
DECLARE curObject CURSOR FOR
select 'Name' = name,
'Owner' = user_name(uid)
from sysobjects
where user_name(uid)=@OldOwner
order by name
OPEN curObject
FETCH NEXT FROM curObject INTO @Name, @Owner
WHILE(@@FETCH_STATUS=0)
BEGIN
if @Owner=@OldOwner
begin
set @OwnerName = @OldOwner + '.' + rtrim(@Name)
exec sp_changeobjectowner @OwnerName, @NewOwner
end
-- select @name,@NewOwner,@OldOwner
FETCH NEXT FROM curObject INTO @Name, @Owner
END
close curObject
deallocate curObject
GO
10、SQL SERVER中直接@环写入数?/p>
declare @i int
set @i=1
while @i<30
begin
insert into test (userid) values(@i)
set @i=@i+1
end
记存储q程中经常用到的本周Q本月，本年函数
Dateadd(wk,datediff(wk,0,getdate()),-1)
Dateadd(wk,datediff(wk,0,getdate()),6)
Dateadd(mm,datediff(mm,0,getdate()),0)
Dateadd(ms,-3,dateadd(mm,datediff(m,0,getdate())+1,0))
Dateadd(yy,datediff(yy,0,getdate()),0)
Dateadd(ms,-3,DATEADD(yy, DATEDIFF(yy,0,getdate())+1, 0))
上面的SQL代码只是一个时间段
Dateadd(wk,datediff(wk,0,getdate()),-1)
Dateadd(wk,datediff(wk,0,getdate()),6)
是表示本周旉D?
下面的SQL的条仉?是查询旉D在本周范围内的:
Where Time BETWEEN Dateadd(wk,datediff(wk,0,getdate()),-1) AND Dateadd(wk,datediff(wk,0,getdate()),6)
而在存储q程?
select @begintime = Dateadd(wk,datediff(wk,0,getdate()),-1)
select @endtime = Dateadd(wk,datediff(wk,0,getdate()),6)
本文来自CSDN博客Q{载请标明出处Qhttp://blog.csdn.net/surfingsoft_mda/archive/2009/11/15/4812371.aspx
本文来自CSDN博客Q{载请标明出处Qhttp://blog.csdn.net/surfingsoft_mda/archive/2009/11/15/4812371.aspx
]]>
数学函数
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?
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^?
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?
S:select sign(-8) value -1
O:select sign(-8) value from dual -1
14.圆周?
S:SELECT PI() value 3.1415926535897931
O:不知?
15.sin,cos,tan 参数都以弧度为单?
例如Qselect sin(PI()/2) value 得到1QSQLServerQ?
16.Asin,Acos,Atan,Atan2 q回弧度
17.弧度角度互换(SQLServerQOracle不知?
DEGREESQ弧?〉角?
RADIANSQ角?〉弧?
数值间比较
18. 求集合最大?
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?
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
21.求字W序?
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四个参数控制出现次?
select INSTR('sdsfasdqe','sd',1,2) value from dual q回6
24.求子?
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?
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?
S:没发?
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?
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?
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?
S:select REPLICATE('abcd',2) value
O:没发?
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?
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?
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?
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?
参数---------------------------------下表需要补?
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?
S:不知?
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?
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?
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?
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?
S:不知?
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?
BST BDT 白o(h)h准时?
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h准时?
MST MDT 山区标准旉
NST U芬兰标准时?
PST PDT 太^z标准时?
YST YDT YUKON标准旉
]]>
说明Q在括号中注明（数|(j)的ؓ(f)数值型函数Q注明ؓ(f)Q字W）(j)的ؓ(f)字符函数Q注明ؓ(f)日期的ؓ(f)日期型函敎ͼ注明为（转换Q的{换型函数Q注明是Q聚l）(j)的ؓ(f)聚组型函敎ͼ不注明的为其他函数?nbsp;
函数名：(x) 说明
abs(x)Q数|(j) q回x的绝对?
add_monthsQxQyQ（日期Q?q回gؓ(f)日期x加上y个月
asciiQxQ（字符Q?q回字符x的十q字表示
avg([distinct|all]x]Q聚l）(j) q回x列的q_?
ceilQxQ（字符Q?q回大于或等于x的最整?
chartorowidQxQ（转换Q?字W串x转换成rowidcd
chrQxQ（字符Q?q回对应于数x的字W集中的字符
concatQxQyQ（字符Q?q回串x和串y接结?
convertQxQy[,z]Q（日期Q?用字W集y来{换字W串xQz为原来的字符?
cosQxQ（数|(j) q回x的余?
coshQxQ（数|(j) q回x的双曲余?
countQ?|distinct|all]xQ（聚组Q?q回查询所得到的行?
dumpQw,[x[,y[,z]]]xQ?q回一个字W串Q含有w的数据类型码Q字节ؓ(f)单位的长度以?qing)内部表CŞ?
expQxQ（数|(j) q回e的xơ幂
floorQxQ（数|(j) q回于或等于x的最大整?
glb([distinct|all]x)Q聚l）(j) q回标签x的最大下?
greatestQx[,y],[,..]Q?q回列表中的最大?
greatest_lb(x[,y],[,…]) q回标签列表中的最大?
hextorawQxQ（字符Q?含?6q制数据的字W串转换成二q制数据
initcapQxQ（字符Q?q回串x首字W大写，其余字符写的结?
instrQw,x[,y[,z]]Q（字符Q?q回串x在串w中的出现位置
instrb(w,x[,y[,z]])Q字W）(j) 同上Q只在多字节字符时有?
last_dayQxQ（日期Q?q回x指定的那个月的最后一?
leastQx[,y][,…]Q?q回列表中的最?
least_ub(x[,y][,…]) q回标签列表中的最?
lengthQxQ（字符Q?q回串x的长?
lengthbQxQ（字符Q?q回串x的字节长?
lnQxQ（数|(j) q回x的自然对?
logQxQyQ（数|(j) q回x为底的y的对?
lowerQxQ（字符Q?q回串x写字母l果
lpadQxQy[,z]Q（字符Q?q回串x左边填充z至长度ؓ(f)y的结?
ltrimQx[,y]Q（字符Q?q回串x左边截去字符集ؓ(f)y后的l果
lubQ[distinct|all]xQ（聚组Q?q回标签x的最上?
max([distinct|all]x)Q聚l）(j) q回x列的最大列?
min([distinct|all]x)Q聚l）(j) q回x列的最列?
modQx,yQ（数|(j) q回x除以y的余?
months_betweenQx,yQ（日期Q?q回x和y之间的月?
new_timeQx,y,zQ（日期Q?q回旉区域y中的旉x在z区域的对应时?
next_dayQx,yQ（日期Q?q回日期x之后W一个名为y的那天的日期
nls_initcatQ字W）(j) 基本同initcapQ只是考虑到语a
nls_lover(x[,y])Q字W）(j) 基本同lowerQ只是考虑到语a
nls_upperQ字W）(j) 基本同upperQ只是考虑到语a
nvlQx,yQ?x为nullq回yQ否则返回x
powerQx,yQ（数|(j) q回x的yơ幂
rawtohexQxQ（转换Q?二q制数据转换?6q制数字的字W串
replace(x,y[,z])Q字W）(j) x中出现y的地Ҏ(gu)换成z
roundQx[,y]Q（数|(j) q回x四舍五入成y位小数的?
roundQx[,y]Q（字符Q?舍入到离日期x最q的那个由y指定的日期单位的W一?
rowidtocharQxQ（转换Q?rowidcd转换成字W型字符?
rpadQx,y[,z]Q（字符Q?q回串x双填充z至长度ؓ(f)y的结?
rtrim(x,y[,z])Q字W）(j) q回串x双截去字符集ؓ(f)y后的l果
signQxQ（数|(j) x为正数、负数?时分别ؓ(f)1、－1?
sinQxQ（数|(j) q回x的正弦?
sinhQxQ（数|(j) q回x的正弦的16q制
soundexQxQ（字符Q?q回x语言发音描述
sqrtQxQ（数|(j) q回x的^Ҏ(gu)
stddev([distinct|all]x)Q聚l）(j) q回数值列x的标准误?
substr(x,y[,z])Q聚l）(j) 从x中的Wy个位|开始取z个字W的子串
sum([distinct|all]x)Q聚l）(j) q回数值列x的合?
sysdateQ日期）(j) q回当前的日期和旉
tanQxQ（数|(j) q回x的正?
tanhQxQ（数|(j) q回x的正切的16q制
to_char(x[,y])Q{换）(j) 一个日期或数字转换成一个字W串
to_date(x[,y])Q{换）(j) 一个字W串转换成日?
to_label(x[,y])Q{换）(j) 一个字W串转换为MLSLABELcd的?
to_multi_bye(x)Q{换）(j) 单字节字符串{换ؓ(f)多字节字W串
to_number(x,y[,z])Q{换）(j) 一个字W串转换成数?
to_single_byte(x)Q{换）(j) 多字节字符串{换ؓ(f)单字节字W串
translate(x,y[,z])Q字W）(j) x中y字符集翻译成z集中相应位置的字W?
trunc(x[,y])Q数|(j) q回x截ؓ(f)y位小数的l果?
trunc(x[,y])Q日期）(j) x舍到由y指定的日期单位的W一天，l果中带有时间部?
uid q回唯一标识当前用户的那个整?
upper(x)Q字W）(j) q回x的大写串
user q回当前用户的数据库用户?
userenv(x) q回关于当前数据库会(x)话的环境信息
variance([distinct|all]x)Q聚l）(j) q回数值列的方?
]]>