你在往sfa_t_backfund做insert的时候触发这个trigger,然后在trigger要去查sfa_t_backfund这个表作sum,这是不允许的。 ORA-04091 table string.string is mutating, trigger/function may not see itCause: A trigger (or a user defined PL/SQL function that is referenced in this statement) attempted to look at (or modify) a table that was in the middle of being modified by the statement which fired it.Action: Rewrite the trigger (or function) so it does not read that table.
Avoiding Mutating TablesOk, so you've just recieved the error: ORA-04091: table XXXX is mutating, trigger/function may not see it and you want to get around that. This short article will describe and demonstrate the various methods of getting around the mutating table error. If you are interested in why you are getting it and in what cases you will get it, please see the Oracle Server Application Developers Guide (click here to read it right now -- this link is to technet.oracle.com. You need a password to access this site but you can get one right away for free). Avoiding the mutating table error is fairly easy. We must defer processing against the mutating or constrainng table until an AFTER trigger. We will consider two cases: Hitting the ORA-4091 in an INSERT trigger or an UPDATE trigger where you only need access to the :new values Hitting the ORA-4091 in a DELETE trigger or an UPDATE trigger where you need to access the :old values Case 1 - you only need to access the :new values This case is the simplest. What we will do is capture the ROWIDS of the inserted or udpated rows. We can then use these ROWIDS in an AFTER trigger to query up the affected rows. It always takes 3 triggers to work around the mutating table error. They are: A before trigger to set the package state to a known, consistent state An after, row level trigger to capture each rows changes An after trigger to actually process the change. As an example -- to show how to do this, we will attempt to answer the following question:
I have a table containing a key/status/effective date combination. When status changes, the values are propagated by trigger to a log table recording the status history. When no RI constraint is in place everything works fine. When an RI trigger enforces a parent-child relationship, the status change logging trigger fails because the parent table is mutating. Propagating the values to the log table implicitly generates a lookup back to the parent table to ensure the RI constraint is satisfied. I do not want to drop the RI constraint. I realize that the status is denormalized. I want it that way. What is a good way to maintain the log?Here is the implementation: SQL> create table parent 2 ( theKey int primary key, 3 status varchar2(1), 4 effDate date 5 ) 6 / Table created. SQL> create table log_table 2 ( theKey int references parent(theKey), 3 status varchar2(1), 4 effDate date 5 ) 6 / Table created. SQL> REM this package is used to maintain our state. We will save the rowids of newly SQL> REM inserted / updated rows in this package. We declare 2 arrays -- one will SQL> REM hold our new rows rowids (newRows). The other is used to reset this array, SQL> REM it is an 'empty' array SQL> create or replace package state_pkg 2 as 3 type ridArray is table of rowid index by binary_integer; 4 4 newRows ridArray; 5 empty ridArray; 6 end; 7 / Package created. SQL> REM We must set the state of the above package to some known, consistent state SQL> REM before we being processing the row triggers. This trigger is mandatory, SQL> REM we *cannot* rely on the AFTER trigger to reset the package state. This SQL> REM is because during a multi-row insert or update, the ROW trigger may fire SQL> REM but the AFTER tirgger does not have to fire -- if the second row in an update SQL> REM fails due to some constraint error -- the row trigger will have fired 2 times SQL> REM but the AFTER trigger (which we relied on to reset the package) will never fire. SQL> REM That would leave 2 erroneous rowids in the newRows array for the next insert/update SQL> REM to see. Therefore, before the insert / update takes place, we 'reset' SQL> create or replace trigger parent_bi 2 before insert or update on parent 3 begin 4 state_pkg.newRows := state_pkg.empty; 5 end; 6 / Trigger created. SQL> REM This trigger simply captures the rowid of the affected row and SQL> REM saves it in the newRows array. SQL> create or replace trigger parent_aifer 2 after insert or update of status on parent for each row 3 begin 4 state_pkg.newRows( state_pkg.newRows.count+1 ) := :new.rowid; 5 end; 6 / Trigger created. SQL> REM this trigger processes the new rows. We simply loop over the newRows SQL> REM array processing each newly inserted/modified row in turn. SQL> create or replace trigger parent_ai 2 after insert or update of status on parent 3 begin 4 for i in 1 .. state_pkg.newRows.count loop 5 insert into log_table 6 select theKey, status, effDate 7 from parent where rowid = state_pkg.newRows(i); 8 end loop; 9 end; 10 / Trigger created. SQL> REM this demonstrates that we can process single and multi-row inserts/updates SQL> REM without failure (and can do it correctly) SQL> insert into parent values ( 1, 'A', sysdate-5 ); 1 row created. SQL> insert into parent values ( 2, 'B', sysdate-4 ); 1 row created. SQL> insert into parent values ( 3, 'C', sysdate-3 ); 1 row created. SQL> insert into parent select theKey+6, status, effDate+1 from parent; 3 rows created. SQL> select * from log_table; THEKEY S EFFDATE ---------- - --------- 1 A 04-AUG-99 2 B 05-AUG-99 3 C 06-AUG-99 7 A 05-AUG-99 8 B 06-AUG-99 9 C 07-AUG-99 6 rows selected. SQL> update parent set status = chr( ascii(status)+1 ), effDate = sysdate; 6 rows updated. SQL> select * from log_table; THEKEY S EFFDATE ---------- - --------- 1 A 04-AUG-99 2 B 05-AUG-99 3 C 06-AUG-99 7 A 05-AUG-99 8 B 06-AUG-99 9 C 07-AUG-99 1 B 09-AUG-99 2 C 09-AUG-99 3 D 09-AUG-99 7 B 09-AUG-99 8 C 09-AUG-99 9 D 09-AUG-99 12 rows selected.
Case 2 - you need to access the :old values This one is a little more involved but the concept is the same. We'll save the actual OLD values in an array (as opposed to just the rowids of the new rows). Using tables of records this is fairly straightforward. Lets say we wanted to implement a flag delete of data -- that is, instead of actually deleting the record, you would like to set a date field to SYSDATE and keep the record in the table (but hide it from queries). We need to 'undo' the delete. In Oracle8.0 and up, we could use "INSTEAD OF" triggers on a view to do this, but in 7.3 the implementation would look like this: SQL> REM this is the table we will be flag deleting from. SQL> REM No one will ever access this table directly, rather, SQL> REM they will perform all insert/update/delete/selects against SQL> REM a view on this table.. SQL> create table delete_demo ( a int, 2 b date, 3 c varchar2(10), 4 hidden_date date default to_date( '01-01-0001', 'DD-MM-YYYY' ), 5 primary key(a,hidden_date) ) 6 / Table created. SQL> REM this is our view. All DML will take place on the view, the table SQL> REM will not be touched. SQL> create or replace view delete_demo_view as 2 select a, b, c from delete_demo where hidden_date = to_date( '01-01-0001', 'DD-MM-YYYY' ) 3 / View created. SQL> grant all on delete_demo_view to public 2 / Grant succeeded. SQL> REM here is the state package again. This time the array is of SQL> REM TABLE%ROWTYPE -- not just a rowid SQL> create or replace package delete_demo_pkg 2 as 3 type array is table of delete_demo%rowtype index by binary_integer; 4 4 oldvals array; 5 empty array; 6 end; 7 / Package created. SQL> REM the reset trigger... SQL> create or replace trigger delete_demo_bd 2 before delete on delete_demo 3 begin 4 delete_demo_pkg.oldvals := delete_demo_pkg.empty; 5 end; 6 / Trigger created. SQL> REM Here, instead of capturing the rowid, we must capture the before image SQL> REM of the row. SQL> REM We cannot really undo the delete here, we are just capturing the deleted SQL> REM data SQL> create or replace trigger delete_demo_bdfer 2 before delete on delete_demo 3 for each row 4 declare 5 i number default delete_demo_pkg.oldvals.count+1; 6 begin 7 delete_demo_pkg.oldvals(i).a := :old.a; 8 delete_demo_pkg.oldvals(i).b := :old.b; 9 delete_demo_pkg.oldvals(i).c := :old.c; 10 end; 11 / Trigger created. SQL> REM Now, we can put the deleted data back into the table. We put SYSDATE SQL> REM in as the hidden_date field -- that shows us when the record was deleted. SQL> create or replace trigger delete_demo_ad 2 after delete on delete_demo 3 begin 4 for i in 1 .. delete_demo_pkg.oldvals.count loop 5 insert into delete_demo ( a, b, c, hidden_date ) 6 values 7 ( delete_demo_pkg.oldvals(i).a, delete_demo_pkg.oldvals(i).b, 8 delete_demo_pkg.oldvals(i).c, sysdate ); 9 end loop; 10 end; 11 / Trigger created. SQL> REM Now, to show it at work... SQL> insert into delete_demo_view values ( 1, sysdate, 'Hello' ); 1 row created. SQL> insert into delete_demo_view values ( 2, sysdate, 'Goodbye' ); 1 row created. SQL> select * from delete_demo_view; A B C ---------- --------- ---------- 1 09-AUG-99 Hello 2 09-AUG-99 Goodbye SQL> delete from delete_demo_view; 2 rows deleted. SQL> select * from delete_demo_view; no rows selected SQL> select * from delete_demo; A B C HIDDEN_DA ---------- --------- ---------- --------- 1 09-AUG-99 Hello 09-AUG-99 2 09-AUG-99 Goodbye 09-AUG-99
to muhuan79 (天 之痕) 其实分析一下这样的两个表完全可以避免使用变异表。 你的触发器这样建就可以避免读取正在触发的表。CREATE OR REPLACE TRIGGER SFA_TR_TOTALBACKFUND AFTER DELETE OR INSERT OR UPDATE ON SFA_T_BACKFUND REFERENCING NEW AS NEW OLD AS OLD FOR EACH ROW DECLARE p_totalBackfund integer; BEGIN IF INSERTING THEN update sfa_t_order set totalBackfund = totalBackfund + :new.backFundmoney where orderID=:new.orderID; ELSIF UPDATING THEN SELECT sum(backFundmoney) INTO p_totalBackfund FROM SFA_T_BACKFUND WHERE OrderID= :old.OrderID; update sfa_t_order set totalBackfund = p_totalBackfund where orderID=:old.OrderID; ELSE SELECT sum(backFundmoney) INTO p_totalBackfund FROM SFA_T_BACKFUND WHERE OrderID= :old.OrderID; update sfa_t_order set totalBackfund = p_totalBackfund where orderID=:old.OrderID; END IF; END;
不好意思上一个刚写一点不小心碰到提交了。 这样建触发器可以避免读取变异表。 CREATE OR REPLACE TRIGGER SFA_TR_TOTALBACKFUND AFTER DELETE OR INSERT OR UPDATE ON SFA_T_BACKFUND REFERENCING NEW AS NEW OLD AS OLD FOR EACH ROW DECLARE p_totalBackfund integer; BEGIN IF INSERTING THEN update sfa_t_order set totalBackfund = totalBackfund + :new.backFundmoney where orderID=:new.orderID; ELSIF UPDATING THEN update sfa_t_order set totalBackfund = totalBackfund +(new.backFundmoney - old.backFundmoney) where orderID=:old.OrderID; ELSE update sfa_t_order set totalBackfund = totalBackfund - old.backFundmoney where orderID=:old.OrderID; END IF; END; 这样就避免了变异表。如果你非要按你的方式操作 wylwyl1130(落雪山林) 说的是对的,要么写一个包。要么建一个临时表,来解决你的变异表的问题。 同时在写一个after的语句级的触发器才能完成你的工作。
ORA-04091 table string.string is mutating, trigger/function may not see itCause: A trigger (or a user defined PL/SQL function that is referenced in this statement) attempted to look at (or modify) a table that was in the middle of being modified by the statement which fired it.Action: Rewrite the trigger (or function) so it does not read that table.
ORA-04091: table XXXX is mutating, trigger/function may not see it and you want to get around that. This short article will describe and demonstrate the various methods of getting around the mutating table error. If you are interested in why you are getting it and in what cases you will get it, please see the Oracle Server Application Developers Guide (click here to read it right now -- this link is to technet.oracle.com. You need a password to access this site but you can get one right away for free). Avoiding the mutating table error is fairly easy. We must defer processing against the mutating or constrainng table until an AFTER trigger. We will consider two cases:
Hitting the ORA-4091 in an INSERT trigger or an UPDATE trigger where you only need access to the :new values
Hitting the ORA-4091 in a DELETE trigger or an UPDATE trigger where you need to access the :old values
Case 1 - you only need to access the :new values
This case is the simplest. What we will do is capture the ROWIDS of the inserted or udpated rows. We can then use these ROWIDS in an AFTER trigger to query up the affected rows.
It always takes 3 triggers to work around the mutating table error. They are:
A before trigger to set the package state to a known, consistent state
An after, row level trigger to capture each rows changes
An after trigger to actually process the change.
As an example -- to show how to do this, we will attempt to answer the following question:
I have a table containing a key/status/effective date combination. When status
changes, the values are propagated by trigger to a log table recording the
status history. When no RI constraint is in place everything works fine.
When an RI trigger enforces a parent-child relationship, the status change
logging trigger fails because the parent table is mutating. Propagating the
values to the log table implicitly generates a lookup back to the parent table
to ensure the RI constraint is satisfied. I do not want to drop the RI constraint. I realize that the status is
denormalized. I want it that way. What is a good way to maintain the log?Here is the implementation: SQL> create table parent
2 ( theKey int primary key,
3 status varchar2(1),
4 effDate date
5 )
6 /
Table created. SQL> create table log_table
2 ( theKey int references parent(theKey),
3 status varchar2(1),
4 effDate date
5 )
6 /
Table created. SQL> REM this package is used to maintain our state. We will save the rowids of newly
SQL> REM inserted / updated rows in this package. We declare 2 arrays -- one will
SQL> REM hold our new rows rowids (newRows). The other is used to reset this array,
SQL> REM it is an 'empty' array SQL> create or replace package state_pkg
2 as
3 type ridArray is table of rowid index by binary_integer;
4
4 newRows ridArray;
5 empty ridArray;
6 end;
7 /
Package created. SQL> REM We must set the state of the above package to some known, consistent state
SQL> REM before we being processing the row triggers. This trigger is mandatory,
SQL> REM we *cannot* rely on the AFTER trigger to reset the package state. This
SQL> REM is because during a multi-row insert or update, the ROW trigger may fire
SQL> REM but the AFTER tirgger does not have to fire -- if the second row in an update
SQL> REM fails due to some constraint error -- the row trigger will have fired 2 times
SQL> REM but the AFTER trigger (which we relied on to reset the package) will never fire.
SQL> REM That would leave 2 erroneous rowids in the newRows array for the next insert/update
SQL> REM to see. Therefore, before the insert / update takes place, we 'reset' SQL> create or replace trigger parent_bi
2 before insert or update on parent
3 begin
4 state_pkg.newRows := state_pkg.empty;
5 end;
6 /
Trigger created. SQL> REM This trigger simply captures the rowid of the affected row and
SQL> REM saves it in the newRows array. SQL> create or replace trigger parent_aifer
2 after insert or update of status on parent for each row
3 begin
4 state_pkg.newRows( state_pkg.newRows.count+1 ) := :new.rowid;
5 end;
6 /
Trigger created. SQL> REM this trigger processes the new rows. We simply loop over the newRows
SQL> REM array processing each newly inserted/modified row in turn. SQL> create or replace trigger parent_ai
2 after insert or update of status on parent
3 begin
4 for i in 1 .. state_pkg.newRows.count loop
5 insert into log_table
6 select theKey, status, effDate
7 from parent where rowid = state_pkg.newRows(i);
8 end loop;
9 end;
10 /
Trigger created. SQL> REM this demonstrates that we can process single and multi-row inserts/updates
SQL> REM without failure (and can do it correctly) SQL> insert into parent values ( 1, 'A', sysdate-5 );
1 row created. SQL> insert into parent values ( 2, 'B', sysdate-4 );
1 row created. SQL> insert into parent values ( 3, 'C', sysdate-3 );
1 row created. SQL> insert into parent select theKey+6, status, effDate+1 from parent;
3 rows created. SQL> select * from log_table; THEKEY S EFFDATE
---------- - ---------
1 A 04-AUG-99
2 B 05-AUG-99
3 C 06-AUG-99
7 A 05-AUG-99
8 B 06-AUG-99
9 C 07-AUG-99 6 rows selected. SQL> update parent set status = chr( ascii(status)+1 ), effDate = sysdate;
6 rows updated. SQL> select * from log_table; THEKEY S EFFDATE
---------- - ---------
1 A 04-AUG-99
2 B 05-AUG-99
3 C 06-AUG-99
7 A 05-AUG-99
8 B 06-AUG-99
9 C 07-AUG-99
1 B 09-AUG-99
2 C 09-AUG-99
3 D 09-AUG-99
7 B 09-AUG-99
8 C 09-AUG-99
9 D 09-AUG-99 12 rows selected.
This one is a little more involved but the concept is the same. We'll save the actual OLD values in an array (as opposed to just the rowids of the new rows). Using tables of records this is fairly straightforward. Lets say we wanted to implement a flag delete of data -- that is, instead of actually deleting the record, you would like to set a date field to SYSDATE and keep the record in the table (but hide it from queries). We need to 'undo' the delete.
In Oracle8.0 and up, we could use "INSTEAD OF" triggers on a view to do this, but in 7.3 the implementation would look like this:
SQL> REM this is the table we will be flag deleting from.
SQL> REM No one will ever access this table directly, rather,
SQL> REM they will perform all insert/update/delete/selects against
SQL> REM a view on this table.. SQL> create table delete_demo ( a int,
2 b date,
3 c varchar2(10),
4 hidden_date date default to_date( '01-01-0001', 'DD-MM-YYYY' ),
5 primary key(a,hidden_date) )
6 /
Table created. SQL> REM this is our view. All DML will take place on the view, the table
SQL> REM will not be touched. SQL> create or replace view delete_demo_view as
2 select a, b, c from delete_demo where hidden_date = to_date( '01-01-0001', 'DD-MM-YYYY' )
3 /
View created. SQL> grant all on delete_demo_view to public
2 /
Grant succeeded. SQL> REM here is the state package again. This time the array is of
SQL> REM TABLE%ROWTYPE -- not just a rowid SQL> create or replace package delete_demo_pkg
2 as
3 type array is table of delete_demo%rowtype index by binary_integer;
4
4 oldvals array;
5 empty array;
6 end;
7 /
Package created. SQL> REM the reset trigger... SQL> create or replace trigger delete_demo_bd
2 before delete on delete_demo
3 begin
4 delete_demo_pkg.oldvals := delete_demo_pkg.empty;
5 end;
6 /
Trigger created. SQL> REM Here, instead of capturing the rowid, we must capture the before image
SQL> REM of the row.
SQL> REM We cannot really undo the delete here, we are just capturing the deleted
SQL> REM data SQL> create or replace trigger delete_demo_bdfer
2 before delete on delete_demo
3 for each row
4 declare
5 i number default delete_demo_pkg.oldvals.count+1;
6 begin
7 delete_demo_pkg.oldvals(i).a := :old.a;
8 delete_demo_pkg.oldvals(i).b := :old.b;
9 delete_demo_pkg.oldvals(i).c := :old.c;
10 end;
11 /
Trigger created. SQL> REM Now, we can put the deleted data back into the table. We put SYSDATE
SQL> REM in as the hidden_date field -- that shows us when the record was deleted. SQL> create or replace trigger delete_demo_ad
2 after delete on delete_demo
3 begin
4 for i in 1 .. delete_demo_pkg.oldvals.count loop
5 insert into delete_demo ( a, b, c, hidden_date )
6 values
7 ( delete_demo_pkg.oldvals(i).a, delete_demo_pkg.oldvals(i).b,
8 delete_demo_pkg.oldvals(i).c, sysdate );
9 end loop;
10 end;
11 /
Trigger created. SQL> REM Now, to show it at work...
SQL> insert into delete_demo_view values ( 1, sysdate, 'Hello' );
1 row created. SQL> insert into delete_demo_view values ( 2, sysdate, 'Goodbye' );
1 row created. SQL> select * from delete_demo_view; A B C
---------- --------- ----------
1 09-AUG-99 Hello
2 09-AUG-99 Goodbye SQL> delete from delete_demo_view;
2 rows deleted. SQL> select * from delete_demo_view;
no rows selected SQL> select * from delete_demo; A B C HIDDEN_DA
---------- --------- ---------- ---------
1 09-AUG-99 Hello 09-AUG-99
2 09-AUG-99 Goodbye 09-AUG-99
其实分析一下这样的两个表完全可以避免使用变异表。
你的触发器这样建就可以避免读取正在触发的表。CREATE OR REPLACE TRIGGER SFA_TR_TOTALBACKFUND
AFTER DELETE OR INSERT OR UPDATE
ON SFA_T_BACKFUND
REFERENCING NEW AS NEW OLD AS OLD
FOR EACH ROW
DECLARE
p_totalBackfund integer;
BEGIN
IF INSERTING THEN
update sfa_t_order set totalBackfund = totalBackfund + :new.backFundmoney where orderID=:new.orderID;
ELSIF UPDATING THEN
SELECT sum(backFundmoney) INTO p_totalBackfund FROM SFA_T_BACKFUND WHERE OrderID= :old.OrderID;
update sfa_t_order set totalBackfund = p_totalBackfund where orderID=:old.OrderID;
ELSE
SELECT sum(backFundmoney) INTO p_totalBackfund FROM SFA_T_BACKFUND WHERE OrderID= :old.OrderID;
update sfa_t_order set totalBackfund = p_totalBackfund where orderID=:old.OrderID;
END IF;
END;
这样建触发器可以避免读取变异表。
CREATE OR REPLACE TRIGGER SFA_TR_TOTALBACKFUND
AFTER DELETE OR INSERT OR UPDATE
ON SFA_T_BACKFUND
REFERENCING NEW AS NEW OLD AS OLD
FOR EACH ROW
DECLARE
p_totalBackfund integer;
BEGIN
IF INSERTING THEN
update sfa_t_order set totalBackfund = totalBackfund + :new.backFundmoney where orderID=:new.orderID;
ELSIF UPDATING THEN
update sfa_t_order set totalBackfund = totalBackfund +(new.backFundmoney - old.backFundmoney) where orderID=:old.OrderID;
ELSE
update sfa_t_order set totalBackfund = totalBackfund - old.backFundmoney where orderID=:old.OrderID;
END IF;
END;
这样就避免了变异表。如果你非要按你的方式操作 wylwyl1130(落雪山林) 说的是对的,要么写一个包。要么建一个临时表,来解决你的变异表的问题。
同时在写一个after的语句级的触发器才能完成你的工作。