Ò׽ؽØÍ¼Èí¼þ¡¢µ¥Îļþ¡¢Ãâ°²×°¡¢´¿ÂÌÉ«¡¢½ö160KB

OracleÖкϲ¢×Ö·û´®×ܽá

ÔÚÊý¾Ý¿âÖо­³£ÒªºÏ²¢×Ö·û´®£¬¶øºÏ²¢×Ö·û´®µÄ·½·¨Óкܶ࣬ÏÖÔÚ×ܽáÈçÏ£º
--´´½¨»á»°¼¶ÁÙʱ±í
create global temporary table TMPA
(
  ID   INTEGER,
  NAME VARCHAR2(10)
)
on commit preserve rows;
--²åÈë¼Ç¼
insert into tmpa select 1,'aa' from dual;
insert into tmpa select 1,'bb' from dual;
insert into tmpa select 1,'cc' from dual;
insert into tmpa select 2,'dd' from dual;
insert into tmpa select 2,'ee' from dual;
insert into tmpa select 3,'ff' from dual;
commit;
--1¡¢sys_conect_by_path·½·¨
select id,max(ltrim(sys_connect_by_path(name,','),',')) as group_name
from
(
select a.*,row_number()over(partition by id order by name) as row_num
from tmpa a
) a
group by id
start with row_num=1
connect by prior id=id and prior row_num= row_num-1
--2¡¢wm_concat·½·¨
select id,wm_concat(name) as group_name from tmpa
group by id;
--3¡¢×Ô¶¨Ò庯Êý·¨
--¶¨Ò庯Êý
create function group_concat(vid number)
return varchar2
as
vResult varchar2(100);
begin
for cur in (select name from tmpa where id=vid) loop
vResult := vResult||cur.name;
end loop;
return vResult;
end;
--²éѯ
select id,group_concat(id) as group_name from tmpa
group by id;
--²éѯµÄ½á¹û
ID GROUP_NAME
1  aa,bb,cc
2  dd,ee
3  ff


Ïà¹ØÎĵµ£º

oracle¸´Ï°£¨Ò»£© Ö®OracleÌåϵ½á¹¹

      ѧϰOracle DBAÒ²°ë¸ö¶àѧÆÚÁË£¬½ñÌìÃÍÈ»²Å·¢ÏÖ£¬Ô­À´ÎÒµÄÊ黹ÊǺÜеģ¬ÉϿβÙ×÷ʱºòÒ²Ö»ÊÇÖªµÀ´ó¸ÅÔõô×ö£¬µ«ÊÇÒªÕæµÄÈ«²¿×Ô¼º×ö£¬¶ø²»È¥·­Ê黹ÊÇÓÐÒ»¶¨µÄÄѶȵģ¬ËùÒÔÄØ£¬½ñÌ쿪ʼ½«DBA´ÓÍ·¸´Ï°Ò»±é£¬Í¬Ê±ÔÙ²Ù×÷Ò»±é¡£
      µÚÒ»Õ£¬Ñ§µÄÊÇOracleµÄÌåϵ½á¹¹£ ......

¡¾oracleÐòÁÐרÌâ¡¿£¨×ªÔØ£©

ORACLEûÓÐÏóSQL SERVERÖÐÒ»ÑùµÄ×ÔÔö¼Ó×ֶΣ¬ÒªÊµÏÖÖ»ÄÜͨ¹ýSEQUENCEÀ´ÊµÏÖ
1.´´½¨ÐòÁУº
create sequence your_seq
nocycle
maxvalue 9999999999
start with 1;
2.ʹÓô¥·¢Æ÷ʵÏÖ×ÔÔö£º
create or replace trigger your_seq_tri
before insert on your_table1 for each row
declare
next_id number;
begin
se ......

Exam : Oracle 1Z0 051

Exam : Oracle 1Z0-051
Title : Oracle Database: SQL Fundamentals I
1. View the Exhibit to examine the description for the SALES table.
Which views can have all DML operations performed on it? (Choose all that apply.)
A. CREATE VIEW v3
AS SELECT * from SALES
WHERE cust_id = 2034
WITH CHECK OPTI ......

oracle ÐÂÔöÓû§,ÉèÖÃȨÏÞ

ÿ¸öOracleÓû§¶¼ÓÐÒ»¸öÃû×ֺͿÚÁî,²¢ÓµÓÐһЩÓÉÆä´´½¨µÄ±í¡¢ÊÓͼºÍÆäËû×ÊÔ´¡£Oracle½ÇÉ«£¨role£©¾ÍÊÇÒ»×éȨÏÞ£¨privilege£©(»òÕßÊÇÿ¸öÓû§¸ù¾ÝÆä״̬ºÍÌõ¼þËùÐèµÄ·ÃÎÊÀàÐÍ)¡£Óû§¿ÉÒÔ¸ø½ÇÉ«ÊÚÓè»ò¸³ÓèÖ¸¶¨µÄȨÏÞ£¬È»ºó½«½ÇÉ«¸³¸øÏàÓ¦µÄÓû§¡£Ò»¸öÓû§Ò²¿ÉÒÔÖ±½Ó¸øÆäËûÓû§ÊÚȨ¡£
    Êý¾Ý¿âϵͳȨÏÞ£¨Dat ......

OracleµÄ¼¸¸öNULLº¯Êý

ƽʱÓõıȽ϶àµÄ£¬¾ÍÊÇNVL£¬Ã»ÔõôÔÚÒâÆäËû¼¸¸ö¡£
NVL ¾Í²»ÓÃ˵ÁË£¬¾ÍÊÇÅжϵÚÒ»¸öÊÇ·ñΪNULL£¬ÊǾÍÓõڶþ¸ö´úÌæ£¬²»ÊǾͷµ»ØµÚÒ»¸ö¡£
NVL2 Ò²ÊÇÅжϵÚÒ»¸öÊÇ·ñΪNULL£¬µ«ÊÇ·µ»ØÖµÈ´²»Í¬¡£µÚÒ»¸öΪNULL£¬¾Í·µ»ØµÚÈý¸ö£¬·ñÔò·µ»ØµÚ¶þ¸ö¡£
NULLIF ÅжÏÁ½¸ö²ÎÊýÊÇ·ñÏàµÈ£¬ÏàµÈ·µ»ØNULL£¬·ñÔò·µ»ØµÚÒ»¸ö²ÎÊý¡£
COALESCE Õâ ......
© 2009 ej38.com All Rights Reserved. ¹ØÓÚE½¡ÍøÁªÏµÎÒÃÇ | Õ¾µãµØÍ¼ | ¸ÓICP±¸09004571ºÅ