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.