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SQL> create table idtable (id number,name varchar2(30));
Table created
SQL> insert into idtable values(10,'ab');
1 row inserted
SQL> insert into idtable values(10,'bc');
1 row inserted
SQL> insert into idtable values(10,'cd');
1 row inserted
SQL> insert into idtable values(20,'hi');
1 row inserted
SQL> insert into idtable values(20,'ij');
1 row inserted
SQL> insert into idtable values(20,'mn');
1 row inserted
SQL> select * from idtable;
        ID NAME
---------- ------------------------------
        10 ab
        10 bc
        10 cd
        20 hi
        20 ij
        20 mn
6 rows selected
SQL> select id,wmsys.wm_concat(name) name from idtable
  2  group by id;
        ID NAME
---------- --------------------------------------------------------------------------------
        10 ab,bc,cd
        20 hi,ij,mn
SQL> select id,wmsys.wm_concat(name) over (order by id) name from idtable;
        ID NAME
---------- --------------------------------------------------------------------------------
        10 ab,bc,cd
        10 ab,bc,cd
        10 ab,bc,cd
        20 ab,bc,cd,hi,ij,mn
        20 ab,bc,cd,hi,ij,mn
        20 ab,bc,cd,hi,ij,mn
6 rows selected
SQL> select id,wmsys.wm_concat(name) over (order by id,name) name from


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oracle ³£¼ûºǫ́½ø³Ì

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• Êý¾Ý¿âд½ø³Ì (DBWn):½«Êý¾Ý¿â»º³åÇø¸ßËÙ»º´æÖеľ­¹ýÐ޸ĵĻº³åÇø(»ÒÊý¾Ý»º ³åÇø)ÒÔÒì²½·½Ê½Ð´Èë´ÅÅÌ
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Oracle dead lock deep research.

Update SQLS will lead dead lock exception. Because by default, it use optimistic lock but not pessimistic lock.
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Optimistic locking offers an elegant solution to the problems o ......

ORACLE 10gÏÂÔØµØÖ·

ORACLE 10gÏÂÔØµØÖ·
Oracle Database 10g Release 2 (10.2.0.1.0) Enterprise/Standard Edition for Microsoft Windows (32-bit)
http://download.oracle.com/otn/nt/oracle10g/10201/10201_database_win32.zip
http://download.oracle.com/otn/nt/oracle10g/10201/10201_client_win32.zip
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