ORA-02055: distributed update operation failed; rollback required解决

最近同事遇到一个奇怪的问题求助，以下奉上国外大神的问题重现及解决方法

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ORA-02055: distributed update operation failed; rollback required

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You call a remote procedure or package over a database link.

Now, on the other side (the remote side), there was an error encountered, but there were already some statements executed successfully.

Now you will need to perform a rollback before you can do a select on the calling side, or you will get this error.

原因：通过数据库链接调用远程存储过程或包。然而，执行过程中远程数据库有报错，但是部分语句已成功执行

措施：在调用端可以查询之前，需要执行回滚操作，否则将获得以上错误提示。

问题重现：

-- First we create some test users

SQL> drop user test1 cascade;

User dropped.

SQL> drop user test2 cascade;

SQL> create user test1 identified by test1;

User created.

SQL> create user test2 identified by test2;

User created.

SQL> grant create session, create table, create trigger, create procedure, create database link to test1, test2;

Grant succeeded.

SQL> alter user test1 quota unlimited on system;

User altered.

SQL> alter user test2 quota unlimited on system;

User altered.

Now we connect to test 2 (remote user) and create a table

SQL> conn test2/test2@XE

Connected.

SQL> create table test2_tab(n number);

Table created.

SQL> insert into test2_tab values(1);

1 row created.

SQL> commit;

Commit complete.

In order to demonstrate this error, we create a trigger on the newly created table, but make sure the trigger fails. In our case, we assign a character to a number field:

create or replace trigger test2_tab_bir

before insert on test2_tab

for each row

begin

:new.n := 'a';

end;

Trigger created.

Connect to test1, create database link

SQL> conn test1/test1@XE

Connected.

SQL>

SQL> create database link test2 connect to test2 identified by test2 using 'XE';

Database link created.

Now we will create a procedure which will first do a successful dml, after that a dml that fails due to the incorrect trigger:

create or replace procedure p is

begin

-- first do a statement that executes ok

update test2_tab@test2 set n=2;

-- next statement will fail because of the invalid trigger

insert into test2_tab@test2 values(1);

end;

Procedure created.

Call the procedure, it will fail:

SQL> exec p

BEGIN p; END;

ERROR at line 1:

ORA-02055: distributed update operation failed; rollback required

ORA-06502: PL/SQL: numeric or value error: character to number conversion error

ORA-06512: at "TEST2.TEST2_TAB_BIR", line 2

ORA-04088: error during execution of trigger 'TEST2.TEST2_TAB_BIR'

ORA-02063: preceding 3 lines from TEST2

ORA-06512: at "TEST1.P", line 4

ORA-06512: at line 1

Now we have a failed distributed transaction, you need to rollback, else you will get the error when selecting ANY table/view

SQL> select sysdate from dual;

select sysdate from dual

ERROR at line 1:

ORA-02067: transaction or savepoint rollback required

-- also happens when oracle itself calls another select recursively (notice the ORA-00604)

SQL> select * from user_2pc_pending;

select * from user_2pc_pending

ERROR at line 1:

ORA-00604: error occurred at recursive SQL level 1

ORA-02067: transaction or savepoint rollback required

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Present By Dylan.