如何在oracle中的複合觸發更新中獲取舊值

Question

我搜索了我的問題，但無法獲得任何解決方案，所以我在這裏發佈它。我正在使用Oracle Database 12c企業版版本12.1.0.1.0 - 64位生產。

我有一個Main_Table，假設有10條記錄，我有一個Log_Table記錄（插入）新表更新時的舊值和新值。

我正在使用複合觸發器（以避免變異錯誤）動態地循環遍歷「Main_Table」的所有列，並通過新的過濾來獲取更新的行記錄。 Primarykey（UID））。

我希望我使用複合觸發權。

我沒有使用:old和:new，因爲我正在動態循環所有列並需要匹配列值。

But it is again giving me mutating error: 
Error report - 
SQL Error: ORA-04091: table Main_Table is mutating, trigger/function may not see it 
ORA-06512: at "Schema.TRG_TEST", line 87 
ORA-04088: error during execution of trigger 'Schema.TRG_TEST' 
04091. 00000 - "table %s.%s is mutating, trigger/function may not see it" 
*Cause: A trigger (or a user defined plsql 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. 


Below is my trigger code: 

create or replace TRIGGER TRG_TEST 
FOR INSERT or UPDATE ON Main_Table 
COMPOUND TRIGGER 
    TYPE NUMBER_TABLE IS TABLE OF NUMBER; 
    tblTABLE2_IDS NUMBER_TABLE; 
    TYPE VARCHAR_TABLE IS TABLE OF VARCHAR(2000); 
    tblTABLE3_IDS VARCHAR_TABLE; 
    TYPE VARCHAR_TABLE1 IS TABLE OF VARCHAR(2000); 
    tblTABLE4_IDS VARCHAR_TABLE1; 

    vcount NUMBER; 
    colCount NUMBER; 
    colCountAfter NUMBER; 
    vvalue VARCHAR2(4000); 
    vcolumn VARCHAR2(4000); 
    sql1 VARCHAR2(4000); 
    dynamicq varchar(4000); 
testv varchar(2000); 
testv1 varchar(2000); 
ssql varchar(2000); 
ssql1 varchar(2000); 
maxsiteid NUMBER; 
newsid varchar(2000); 
newstid varchar(2000); 
newuid varchar(2000); 
--Executed before DML statement 

    BEFORE STATEMENT IS 
    BEGIN 
tblTABLE2_IDS := NUMBER_TABLE(); 
    tblTABLE3_IDS:= VARCHAR_TABLE(); 
    tblTABLE4_IDS:= VARCHAR_TABLE1(); 
    IF UPDATING THEN 
    dbms_output.put_line('Before Statement - In Updating'); 
     --dbms_output.put_line('Before Each Row - In Updating'); 
     -- tblTABLE2_IDS.EXTEND; 
     --tblTABLE2_IDS(tblTABLE2_IDS.LAST) := :new.UID; 
     END IF; 
    END BEFORE STATEMENT; 

    --Executed before each row change- :NEW, :OLD are available 
    BEFORE EACH ROW IS 
    BEGIN 
     IF UPDATING THEN 
     dbms_output.put_line('Before Each Row - In Updating'); 
     tblTABLE2_IDS.EXTEND; 
     tblTABLE2_IDS(tblTABLE2_IDS.LAST) := :new.UID; 
    -- FOR columnlist IN 
     --(SELECT COLUMN_NAME AS COLUMN_NAME FROM all_tab_columns WHERE lower(TABLE_NAME) = 'Main_Table' 
     -- AND lower(COLUMN_NAME) NOT IN ('s_id' ,'msid' ,'st' ,'u_id' ,'db_flag')) 

     --LOOP 
     --colCount:=colCount+1; 
     --ssql1:='select '||columnlist.COLUMN_NAME||' from Main_Table where UID='||tblTABLE2_IDS(tblTABLE2_IDS.LAST)||''; 
     --dbms_output.put_line(ssql1); 
     --execute immediate ssql1 into testv; 
     --tblTABLE3_IDS(colCount):=testv; 
     --dbms_output.put_line(testv); 
     --END LOOP; 
      END IF; 
    END BEFORE EACH ROW; 

--Executed aftereach row change- :NEW, :OLD are available 
    AFTER EACH ROW IS 
    BEGIN 

    IF UPDATING THEN 
     dbms_output.put_line('After Each Row - In Updating'); 
     FOR columnlist IN 
     (SELECT COLUMN_NAME AS COLUMN_NAME FROM all_tab_columns WHERE lower(TABLE_NAME) = 'Main_Table' 
     AND lower(COLUMN_NAME) NOT IN ('s_id' ,'msid' ,'st' ,'u_id' ,'db_flag')) 

     LOOP 
     colCount:=colCount+1; 
     ssql1:='select '||columnlist.COLUMN_NAME||' from Main_Table where UID='||tblTABLE2_IDS(tblTABLE2_IDS.LAST)||''; 
     dbms_output.put_line(ssql1); 
     execute immediate ssql1 into testv; 
     tblTABLE3_IDS(colCount):=testv; 
     dbms_output.put_line(testv); 
     END LOOP; 
      END IF; 
    END AFTER EACH ROW; 

--Executed after DML statement 
    AFTER STATEMENT IS 
    BEGIN 

     IF UPDATING THEN 
      dbms_output.put_line('After Statement - In Updating'); 
      FOR columnlist IN 
     (SELECT COLUMN_NAME AS COLUMN_NAME FROM all_tab_columns WHERE lower(TABLE_NAME) = 'Main_Table' 
     AND lower(COLUMN_NAME) NOT IN ('s_id' ,'msid' ,'st' ,'u_id' ,'db_flag')) 

     LOOP 
     colCountAfter:=colCountAfter+1; 
     dbms_output.put_line('loop started'); 

     ssql1:='select '||columnlist.COLUMN_NAME||' from Main_Table where UID='||tblTABLE2_IDS(tblTABLE2_IDS.LAST)||''; 

     execute immediate ssql1 into testv1; 
     dbms_output.put_line(testv); 
     tblTABLE3_IDS(colCountAfter):=testv1; 

     IF ((testv) IS NOT NULL) THEN 
     FOR i IN tblTABLE3_IDS.FIRST..tblTABLE2_IDS.LAST LOOP 
     dbms_output.put_line('Values No :' ||i||' is ' || tblTABLE3_IDS(i) || ' and ' ||tblTABLE4_IDS(i)); 
     IF(tblTABLE3_IDS(i)=tblTABLE4_IDS(i)) THEN 
     dbms_output.put_line(testv1); 


     ELSE 
     -- dbms_output.put_line('select :new.'|| columnlist.COLUMN_NAME||' from dual'); 
     dbms_output.put_line(testv1);   


     INSERT INTO Log_Table 
       (
       user_id, 
       log_action, 
       log_table_name, 
       schema_name, 
       log_column_name, 
       col_old_val, 
       col_new_val, 
       ne_type, 
       ne_id, 
       system_id 
      ) 
       VALUES 
       (
       newuid, 
       'UPDATE', 
       'Main_Table', 
       'SCHEMA' 
       ,columnlist.COLUMN_NAME 
       ,tblTABLE3_IDS(i) 
       ,tblTABLE4_IDS(i) 
       ,'S' 
       ,newstid 
       ,newsid 
      ); 
     END IF; 
     END LOOP; 


     END IF; 
     END LOOP; 
      END IF; 

    END AFTER STATEMENT; 
    END TRG_TEST; 

最初我曾試圖訪問更新表中「各行之前」然後我試圖訪問它，同樣的錯誤在這兩種情況下，「每一行後」。

即使在使用複合觸發器後，我仍然很難找到解決方案，但是對於插入操作我也達到了同樣的效果。

任何人都可以幫助如何實現它。提前致謝。

Answer 1

通常，after語句的行級觸發器足以填充日誌表。 舊的和新的列值可用於舊的和新的僞記錄。

一個很簡單的例子：

create or replace trigger my_trigger 
    after insert or update on my_table 
    for each row 
declare 

    begin 

     if inserting 
     then 
      insert into logging table 
      (id 
      ,my_column_old 
      ,my_column_new) 
      values 
      (:new.id 
      ,null  -- no old value in case of insert 
      ,:new.my_column); 
     else 
      insert into logging table 
      (id 
      ,my_column_old 
      ,my_column_new) 
      values 
      (:new.id 
      ,:old.my_column 
      ,:new.my_column); 
     end if; 
    end; 

Answer 2

當我從你想跟蹤新增列的歷史您的意見一個瞭解（用戶可以添加和刪除列），你想不重新編譯觸發。

然後你可以使用Oracle Total Recall

令人高興的是你有甲骨文12C EE（最多bug是固定的）。