关于create database link的问题。急，快点进来，谢谢

sforat 2011-12-13 04:22:28

我是这样写的
create database link db1_link
connect to user identified by pwd
using '(DESCRIPTION =
(ADDRESS_LIST =
(ADDRESS = (PROTOCOL = TCP)(HOST = liuip)(PORT = 1521))
)
(CONNECT_DATA =
(SERVICE_NAME = database_name)
)
)';

其实很简单，但是问题是执行报错。说 identified by pwd pwd有问题
我在考虑要不要加单引号'pwd' 加了也不行，不加也报错。为什么为什么？？急。

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切换为时间正序

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qinglang1987 2011-12-15

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create database link db1_link
connect to user identified by "pwd"
using '(DESCRIPTION =
(ADDRESS_LIST =
(ADDRESS = (PROTOCOL = TCP)(HOST = liuip)(PORT = 1521))
)
(CONNECT_DATA =
(SERVICE_NAME = database_name)
)
)';

这样就好了

qinglang1987 2011-12-15

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[Quote=引用楼主 sforat 的回复:]
我是这样写的
create database link db1_link
connect to user identified by pwd
using '(DESCRIPTION =
(ADDRESS_LIST =
(ADDRESS = (PROTOCOL = TCP)(HOST = liuip)(PORT = 1521))
)
(CONNECT_DAT……
[/Quote]

pwd 两边加上双引号“” 不是单引号‘’

s3068770 2011-12-15

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(DESCRIPTION = (ADDRESS_LIST = (ADDRESS = (PROTOCOL = TCP)(HOST = liuip)(PORT = 1521)) ) (CONNECT_DATA = (SERVICE_NAME = database_name) ) )
不能有换行。

tlx20093A 2011-12-15

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这样也行：
create database link db1_link
connect to
username identified by pwd
using 'oracle_sid';

rfb0204421 2011-12-15

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我心飞翔 2011-12-13

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呵呵，一场虚惊!
不过还是恭喜一下了。

sforat 2011-12-13

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我自己知道了。原来密码不能数字开头。。。

争取今天 2011-12-13

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user 是oracle关键字,如果要用它做对象名,用双引号括上.
最后别用关键字,否则用起来也麻烦

sforat 2011-12-13

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有人吗

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47.怎么实现一条记录根据条件多表插入 9i以上可以通过Insert all语句完成，仅仅是一个语句，如： INSERT ALL WHEN (id=1) THEN INTO table_1 (id, name) values(id,name) WHEN (id=2) THEN INTO table_2 (id, name) values(id,name) ELSE INTO table_other (id, name) values(id, name) SELECT id,name FROM a; 如果没有条件的话，则完成每个表的插入，如 INSERT ALL INTO table_1 (id, name) values(id,name) INTO table_2 (id, name) values(id,name) INTO table_other (id, name) values(id, name) SELECT id,name FROM a; 48.如何实现行列转换 <1>、固定列数的行列转换如 student subject grade --------------------------- student1 语文 80 student1 数学 70 student1 英语 60 student2 语文 90 student2 数学 80 student2 英语 100 ... 转换为语文数学英语 student1 80 70 60 student2 90 80 100 ... 语句如下： select student,sum(decode(subject,\'语文\', grade,null)) \"语文\", sum(decode(subject,\'数学\', grade,null)) \"数学\", sum(decode(subject,\'英语\', grade,null)) \"英语\" from table group by student <2>、不定列行列转换如 c1 c2 -------------- 1 我 1 是 1 谁 2 知 2 道 3 不 ... 转换为 1 我是谁 2 知道 3 不这一类型的转换必须借助于PL/SQL来完成，这里给一个例子 CREATE OR REPLACE FUNCTION get_c2(tmp_c1 NUMBER) RETURN VARCHAR2 IS Col_c2 VARCHAR2(4000); BEGIN FOR cur IN (SELECT c2 FROM t WHERE c1=tmp_c1) LOOP Col_c2 := Col_c2||cur.c2; END LOOP; Col_c2 := rtrim(Col_c2,1); RETURN Col_c2; END; / SQL> select distinct c1 ,get_c2(c1) cc2 from table;即可 --例子： create table okcai_1 ( user_id varchar2(10), user_number varchar2(10), user_num number(8) ) user_id user_number user_num --------------------- 1 123 2 1 456 5 1 789 6 2 11 2 2 22 3 2 33 4 2 44 5 2 55 6 2 66 7 2 77 8 3 1234 1 3 5678 2 方式一： create or replace function get_col( p_userId number, p_col number ) return varchar as v_tmp varchar2(255); begin select user_number||chr(9)||user_num into v_tmp from (select user_number,user_num,rownum row_id from okcai_1 where user_id = p_userId) a where row_id = p_col; return ltrim(v_tmp); --return v_tmp; end; 然后 select distinct user_id,get_col(user_id,1),get_col(user_id,2),get_col(user_id,3) .... from okcai_1 方式二： create or replace function get_col( p_userId number, p_col number ) return varchar as v_tmp varchar2(255); begin select user_number||chr(9)||user_num into v_tmp from (select user_number,user_num,rownum row_id from okcai_1 where user_id = p_userId) a where row_id = p_col; return ltrim(v_tmp); --return v_tmp; end; select distinct user_id,get_col_new(user_id) from okcai_1; 49.怎么设置存储过程的调用者权限普通存储过程都是所有者权限，如果想设置调用者权限，请参考如下语句 create or replace procedure ...() AUTHID CURRENT_USER As begin ... end; 50.Oracle有哪些常见关键字详细信息可以查看v$reserved_words视图 51.怎么查看数据库参数 <1> show parameter 参数名如通过show parameter spfile可以查看9i是否使用spfile文件其中参数名是可以匹配的。比如show parameter cursor ,则会显示跟cursor相关的参数 <2> select * from v$parameter <3> 除了这部分参数，Oracle还有大量隐含参数，可以通过如下语句查看: SELECT NAME ,VALUE ,decode(isdefault, \'TRUE\',\'Y\',\'N\') as \"Default\" ,decode(ISEM,\'TRUE\',\'Y\',\'N\') as SesMod ,decode(ISYM,\'IMMEDIATE\', \'I\', \'DEFERRED\', \'D\', \'FALSE\', \'N\') as SysMod ,decode(IMOD,\'MODIFIED\',\'U\', \'SYS_MODIFIED\',\'S\',\'N\') as Modified ,decode(IADJ,\'TRUE\',\'Y\',\'N\') as Adjusted ,description FROM ( --GV$SYSTEM_PARAMETER SELECT x.inst_id as instance ,x.indx+1 ,ksppinm as NAME ,ksppity ,ksppstvl as VALUE ,ksppstdf as isdefault ,decode(bitand(ksppiflg/256,1),1,\'TRUE\',\'FALSE\') as ISEM ,decode(bitand(ksppiflg/65536,3), 1,\'IMMEDIATE\',2,\'DEFERRED\',\'FALSE\') as ISYM ,decode(bitand(ksppstvf,7),1,\'MODIFIED\',\'FALSE\') as IMOD ,decode(bitand(ksppstvf,2),2,\'TRUE\',\'FALSE\') as IADJ ,ksppdesc as DESCRIPTION FROM x$ksppi x ,x$ksppsv y WHERE x.indx = y.indx AND substr(ksppinm,1,1) = \'_\' AND x.inst_id = USERENV(\'Instance\') ) ORDER BY NAME 52.怎样建立基于函数索引 8i以上版本，确保 Query_rewrite_enabled=true Query_rewrite_integrity=trusted Compatible=8.1.0以上 Create index indexname on table (function(field)); 53.怎么样移动表或表分区 [A]移动表的语法 Alter table tablename move [Tablespace new_name Storage(initial 50M next 50M pctincrease 0 pctfree 10 pctused 50 initrans 2) nologging] 移动分区的语法 alter table tablename move (partition partname) [update global indexes] 之后之后必须重建索引 Alter index indexname rebuild 如果表有Lob段，那么正常的Alter不能移动Lob段到别的表空间，而仅仅是移动了表段，可以采用如下的方法移动Lob段 alter table tablename move lob(lobsegname) store as (tablespace newts); 54.怎么样修改表的列名 [A]9i以上版本可以采用rname命令 ALTER TABLE UserName.TabName RENAME COLUMN SourceColumn TO DestColumn 9i以下版本可以采用create table …… as select * from SourceTable的方式。另外，8i以上可以支持删除列了 ALTER TABLE UserName.TabName SET UNUSED (ColumnName) CASCADE CONSTRAINTS ALTER TABLE UserName.TabName DROP (ColumnName) CASCADE CONSTRAINTS 55.case的用法在sql语句中 CASE test_value WHEN expression1 THEN value1 [[WHEN expression2 THEN value2] [...]] [ELSE default_value] END 比如1 SELECT last_name, job_id, salary CASE job_id WHEN \'IT_PROG\' THEN 1.10*salary WHEN \'ST_CLERK\' THEN 1.15*salary WHEN \'SA_REP\' THEN 1.20*salary ELSE salary END \"REVISED_SALARY\" FROM employees 比如2 select case when real_charge>=20000 and real_charge<30000 then 5000 when real_charge>=30000 and real_charge<40000 then 9000 when real_charge>=40000 and real_charge<50000 then 10000 when real_charge>=50000 and real_charge<60000 then 14000 when real_charge>=60000 and real_charge<70000 then 18000 when real_charge>=70000 and real_charge<80000 then 19000 when real_charge>=80000 and real_charge<90000 then 24000 when real_charge>=90000 and real_charge<100000 then 27000 when real_charge>=100000 and real_charge<110000 then 27000 when real_charge>=110000 and real_charge<120000 then 29000 when real_charge>=120000 then 36000 else 0 end ,acc_id,user_id,real_charge from okcai_jh_charge_200505 在存储过程中 case v_strGroupClassCode when \'1\' then v_nAttrNum := v_nAttrNum + 300; v_strAttrFlag := \'1\'||substr(v_strAttrFlag,2,7); when \'2\' then v_nAttrNum := v_nAttrNum + 200; v_strAttrFlag := \'2\'||substr(v_strAttrFlag,2,7); else NULL; end case; 注意的是存储过程和sql语句有的细微差别是用end case，而不是end。语句后面跟\";\"

一种利用dblink模式： 1 Create public database link xxxx connect to xxxx identified by xxxxusing 'xxxx'; --select 'drop table '||trim(xxxx)||';' from dt_tabinfo where dw_sysid = '0005' --2 select ...

无法在Linux上使用绝对路径创建Docker卷(Can't create Docker volume using absolute path on Linux)当我试图运行一个Docker容器时，我想通过一个目录共享一些数据(我添加了重点)时收到以下错误消息：## [错误] / usr / bin / docker：来自守护进程的错误响应：create -v / opt / vsts / wor...

欢迎来到《数据库导论》课程。我是来自斯坦福大学的Jennifer Whittom。在这门课程中，我们将学习数据库及数据库管理系统的使用，主要从数据库应用的设计者、用户和开发者的角度来探讨。我将从一个非常长的句子开始，描述数据库管理系统为应用提供的功能。它主要提供了处理大量数据的方法，但让我们更详细地看看。它提供的功能可以用一个长句子来总结：高效、可靠。方便、安全的多用户存储和访问大量持久性数据。因此，我将在稍后更详细地讲解每一个形容词，但我想先提到的是，数据库系统在今天的世界中非常普及。

转载自：http://www.cnblogs.com/xiaoL/p/4153655.html http://wenku.baidu.com/link?url=liS0_3fAyX2uXF5MAEQxMOj3YIY4UCcQM4gPfPzHfFcHBXuJTE8rANrwu6GXwdzbmvdVkWA66z9KOaFu6O_0PrhWxCEUd4ECYzqC7QL82hq

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