stream是 oracle 11g  支持的数据同步技术, 虽然该技术已经不是什么新技术, 但目前国内采用该技术开发的软件不多见. stream 同步软件项目参与近一年, 近期软件上线实施, 效果不是很理想.  同步过程中会偶尔出现  ORA-00001, ORA-26786, ORA-26787 等常见错误.  经过几天的的研究, 开发了一个守护平台,采用 java 平台和存储过程相结合的方式自动处理以上错误. 我写的这些算法具有通用性, 不需要手工指定删除表的列,通过实践具有较好的效果. 相对于set_update_conflict_handler这个方法,简单易用. java 平台代码便不开源了, 其实核心的思想还是在存储过程中, 特分享给大家, 共同进步.

自定义 type

create or replace type myvarray_list as varray(300) of varchar2(50)
CREATE OR REPLACE PROCEDURE EXECUTE_TRANSACTION_1(applyname IN VARCHAR2,ltxnid IN VARCHAR2) IS

    i      NUMBER;

    x       NUMBER;

    loopdog NUMBER;

    txnid  VARCHAR2(30);

    source VARCHAR2(128);

    msgno  NUMBER;

    msgcnt NUMBER;

    errno  NUMBER;

    errmsg VARCHAR2(2000);

    lcr    ANYDATA;

    rowlcr    SYS.LCR$_ROW_RECORD;

    typenm    VARCHAR2(61);

    res       NUMBER;

    command      VARCHAR2(10);

    old_values   SYS.LCR$_ROW_LIST;

    new_values   SYS.LCR$_ROW_LIST;

    v_code  NUMBER;

    v_errm  VARCHAR2(1024);

    object_owner     VARCHAR2(30);

      object_name      VARCHAR2(40);

      key_column       myvarray_list;

      remove_column   myvarray_list;

      remove_flag     NUMBER;

      remove_count    NUMBER;

BEGIN

    SELECT LOCAL_TRANSACTION_ID,

         SOURCE_DATABASE,

         MESSAGE_NUMBER,

         MESSAGE_COUNT,

         ERROR_NUMBER,

         ERROR_MESSAGE

          INTO txnid, source, msgno, msgcnt, errno, errmsg

          FROM DBA_APPLY_ERROR

          WHERE LOCAL_TRANSACTION_ID =  ltxnid;

    DBMS_OUTPUT.PUT_LINE(' --- Local Transaction ID: ' || txnid);

      DBMS_OUTPUT.PUT_LINE(' --- Source Database: ' || source);

      DBMS_OUTPUT.PUT_LINE(' ---Error in Message: '|| msgno);

      DBMS_OUTPUT.PUT_LINE(' ---Error Number: '||errno);

      DBMS_OUTPUT.PUT_LINE(' ---Message Text: '||errmsg);

    i := msgno;

    loopdog :=0;

      WHILE i <= msgcnt LOOP

          loopdog :=loopdog+1;

        DBMS_OUTPUT.PUT_LINE('---message: ' || i);

        lcr := DBMS_APPLY_ADM.GET_ERROR_MESSAGE(i, txnid); -- gets the LCR

        typenm := lcr.GETTYPENAME();

        DBMS_OUTPUT.PUT_LINE('type name: ' || typenm);

        IF (typenm = 'SYS.LCR$_ROW_RECORD') THEN

            res := lcr.GETOBJECT(rowlcr);

            command := rowlcr.GET_COMMAND_TYPE();

            DBMS_OUTPUT.PUT_LINE('command type name: ' || command);

            IF command = 'INSERT' THEN

                rowlcr.SET_COMMAND_TYPE('DELETE');

                new_values := rowlcr.GET_VALUES('new');

                -- Set the old values in the row LCR to the new values in the row LCR

                rowlcr.SET_VALUES('old', new_values);

                -- Set the old values in the row LCR to NULL

                rowlcr.SET_VALUES('new', NULL);

                old_values := rowlcr.GET_VALUES('old');

                -- Apply the row LCR as an DELETE FROM  the  table

                object_name :=rowlcr.GET_OBJECT_NAME();

                object_owner :=rowlcr.GET_OBJECT_OWNER();

                key_column := myvarray_list();   --init array.

                i :=1;

                FOR emm IN (select DISTINCT CO.COLUMN_NAME from

                                                  DBA_cons_columns CO, dba_constraints PK

                                                      where CO.constraint_name = PK.constraint_name

                                                          AND CO.OWNER = PK.OWNER

                                                          AND PK.constraint_type IN ('P','C','U')

                                                          and PK.table_name = object_name

                                                          AND PK.OWNER=object_owner) LOOP

                    DBMS_OUTPUT.PUT_LINE('key column ' || emm.COLUMN_NAME);

                    key_column.extend;

                    key_column(i) := emm.COLUMN_NAME;

                    i :=i+1;

                END LOOP;

                remove_column := myvarray_list();   --init array.

                  remove_count := 1;

                FOR i in 1..old_values.count LOOP

                      IF old_values(i) IS NOT NULL THEN

                        --DBMS_OUTPUT.PUT_LINE('old(' || i || '): ' || old_values(i).column_name);

                        x :=1;

                        remove_flag :=1;

                          WHILE x <= key_column.count AND remove_flag=1 loop

                             --dbms_output.put_line('key_column('||x||')='||key_column(x));

                             IF old_values(i).column_name = key_column(x) THEN

                                 remove_flag :=0;

                             END IF;

                             x :=x +1;

                         END loop;

                         IF remove_flag = 1 then

                             remove_column.extend;

                            remove_column(remove_count) := old_values(i).column_name;

                            remove_count :=remove_count+1;

                         END IF;

                      END IF;

                END LOOP;

                FOR x in 1..remove_column.count loop

                     dbms_output.put_line('remove_column('||x||')='||remove_column(x));

                     rowlcr.DELETE_COLUMN(remove_column(x),'old');

                 END loop;

                rowlcr.EXECUTE(true);

            END IF;

            BEGIN

            --dbms_apply_adm.execute_all_errors(applyname);

            dbms_apply_adm.EXECUTE_ERROR(ltxnid);

            return;

            EXCEPTION when OTHERS then

                SELECT MESSAGE_NUMBER  INTO  i FROM DBA_APPLY_ERROR  WHERE LOCAL_TRANSACTION_ID =  ltxnid;

                v_code := SQLCODE;

                v_errm := SUBSTR(SQLERRM, 1, 1024);

                DBMS_OUTPUT.PUT_LINE('Error message: ' || v_errm);

                IF loopdog > msgcnt then

                    RAISE_APPLICATION_ERROR(-20002,'Insert or Delete error. please check your procedure.');

                ELSIF v_code = -1 then

                    DBMS_OUTPUT.PUT_LINE('Error code(-1): ' || v_code);

                    --null;

                ELSIF v_code = -26786 then

                    DBMS_OUTPUT.PUT_LINE('Error code(-26786): ' || v_code);

                    RAISE_APPLICATION_ERROR(-20786,v_errm);

                ELSIF v_code = -26787 then

                    DBMS_OUTPUT.PUT_LINE('Error code(-26787): ' || v_code);

                    RAISE_APPLICATION_ERROR(-20787,v_errm);

                ELSE

                    RAISE_APPLICATION_ERROR(-20000,v_errm);

                END IF;

            END;

        END IF;

    END LOOP;      --loop

END EXECUTE_TRANSACTION_1;

--需要这两个 权限

--grant select on dba_constraints to DWESBSTREAMUSER;

--granT select on DBA_cons_columns to DWESBSTREAMUSER;

ORA-00001 错误是目标端存在数据,但是存在冲突列, 这里储存储过程的思想是根据唯一列删除目标端的对应行, 并将LCR 是old 值插入到目标端.

-----------------------------------------------------------------------------------------------------------------------------------

CREATE OR REPLACE PROCEDURE EXECUTE_TRANSACTION_26786(applyname IN VARCHAR2,ltxnid IN VARCHAR2) IS

    i      NUMBER;

    x       NUMBER;

    loopdog NUMBER;

    txnid  VARCHAR2(30);

    source VARCHAR2(128);

    msgno  NUMBER;

    msgcnt NUMBER;

    errno  NUMBER;

    errmsg VARCHAR2(2000);

    lcr    ANYDATA;

    rowlcr    SYS.LCR$_ROW_RECORD;

    typenm    VARCHAR2(61);

    res       NUMBER;

    command      VARCHAR2(10);

    old_values   SYS.LCR$_ROW_LIST;

    new_values   SYS.LCR$_ROW_LIST;

    v_code  NUMBER;

    v_errm  VARCHAR2(1024);

    object_owner     VARCHAR2(30);

      object_name      VARCHAR2(40);

      key_column       myvarray_list;

      remove_column   myvarray_list;

      remove_flag     NUMBER;

      remove_count    NUMBER;

BEGIN

    SELECT LOCAL_TRANSACTION_ID,

         SOURCE_DATABASE,

         MESSAGE_NUMBER,

         MESSAGE_COUNT,

         ERROR_NUMBER,

         ERROR_MESSAGE

          INTO txnid, source, msgno, msgcnt, errno, errmsg

          FROM DBA_APPLY_ERROR

          WHERE LOCAL_TRANSACTION_ID =  ltxnid;

    DBMS_OUTPUT.PUT_LINE('--- Local Transaction ID: ' || txnid);

      DBMS_OUTPUT.PUT_LINE('--- Source Database: ' || source);

      DBMS_OUTPUT.PUT_LINE('---Error in Message: '|| msgno);

      DBMS_OUTPUT.PUT_LINE('---Error Number: '||errno);

      DBMS_OUTPUT.PUT_LINE('---Message Text: '||errmsg);

    i := msgno;

    loopdog :=0;

      WHILE i <= msgcnt LOOP

          loopdog :=loopdog+1;

          DBMS_OUTPUT.PUT_LINE('---message: ' || i);

        lcr := DBMS_APPLY_ADM.GET_ERROR_MESSAGE(i, txnid); -- gets the LCR

        typenm := lcr.GETTYPENAME();

        DBMS_OUTPUT.PUT_LINE('type name: ' || typenm);

        IF (typenm = 'SYS.LCR$_ROW_RECORD') THEN

            res := lcr.GETOBJECT(rowlcr);

            command := rowlcr.GET_COMMAND_TYPE();

            DBMS_OUTPUT.PUT_LINE('command type name: ' || command);

            IF command IN ('DELETE','UPDATE') THEN

                rowlcr.SET_COMMAND_TYPE('DELETE');

                old_values := rowlcr.GET_VALUES('old');

                -- Set the new values in the row LCR to NULL

                rowlcr.SET_VALUES('new', NULL);

                -- Apply the row LCR as an DELETE FROM  the  table  --

                object_name :=rowlcr.GET_OBJECT_NAME();

                object_owner :=rowlcr.GET_OBJECT_OWNER();

               ---------------------------------------------------------------------------------------

                key_column := myvarray_list();   --init array.

                i :=1;

                FOR emm IN (select DISTINCT CO.COLUMN_NAME from

                                                  DBA_cons_columns CO, dba_constraints PK

                                                      where CO.constraint_name = PK.constraint_name

                                                          AND CO.OWNER = PK.OWNER

                                                          AND PK.constraint_type IN ('P','C','U')

                                                          and PK.table_name = object_name

                                                          AND PK.OWNER=object_owner) LOOP

                    DBMS_OUTPUT.PUT_LINE('key column ' || emm.COLUMN_NAME);

                    key_column.extend;

                    key_column(i) := emm.COLUMN_NAME;

                    i :=i+1;

                END LOOP;

                -----------------------------------------------------------------------------------

                remove_column := myvarray_list();   --init array.

                  remove_count := 1;

                FOR i in 1..old_values.count LOOP

                      IF old_values(i) IS NOT NULL  THEN

                        --DBMS_OUTPUT.PUT_LINE('old(' || i || '): ' || old_values(i).column_name);

                        x :=1;

                        remove_flag :=1;

                          WHILE x <= key_column.count AND remove_flag=1 loop

                             --dbms_output.put_line('key_column('||x||')='||key_column(x));

                             IF old_values(i).column_name = key_column(x) THEN

                                 remove_flag :=0;

                             END IF;

                             x :=x +1;

                         END loop;

                         IF remove_flag = 1 then

                             remove_column.extend;

                            remove_column(remove_count) := old_values(i).column_name;

                            remove_count :=remove_count+1;

                         END IF;

                      END IF;

                END LOOP;    

                -----------------------------------------------------------------------------

                FOR x in 1..remove_column.count loop

                     dbms_output.put_line('remove_column('||x||')='||remove_column(x));

                     rowlcr.DELETE_COLUMN(remove_column(x),'old');

                 END loop;

                rowlcr.EXECUTE(true);

                DBMS_OUTPUT.PUT_LINE('DELETE target old new ');

                --- INSERT NEW DATA--

                rowlcr.SET_COMMAND_TYPE('INSERT');

                rowlcr.SET_VALUES('new',old_values);

                rowlcr.SET_VALUES('old',NULL);

                rowlcr.EXECUTE(true);

                DBMS_OUTPUT.PUT_LINE('insert source old new');

            END IF;

            BEGIN

            --dbms_apply_adm.execute_all_errors(applyname);

            dbms_apply_adm.EXECUTE_ERROR(ltxnid);

            return;

            EXCEPTION when OTHERS then

                SELECT MESSAGE_NUMBER  INTO  i FROM DBA_APPLY_ERROR  WHERE LOCAL_TRANSACTION_ID =  ltxnid;

                v_code := SQLCODE;

                v_errm := SUBSTR(SQLERRM, 1, 1024);

                DBMS_OUTPUT.PUT_LINE('Error message: ' || v_errm);

                IF loopdog > msgcnt then

                    RAISE_APPLICATION_ERROR(-20002,'Insert or Delete error. please check your procedure.');

                ELSIF v_code = -26786 then

                    DBMS_OUTPUT.PUT_LINE('Error code(-26786): ' || v_code);

                ELSIF v_code = -26787 then

                    DBMS_OUTPUT.PUT_LINE('Error code(-26787): ' || v_code);

                    RAISE_APPLICATION_ERROR(-20787,v_errm);

                ELSIF v_code = -1 then

                    DBMS_OUTPUT.PUT_LINE('Error code(-1): ' || v_code);

                    RAISE_APPLICATION_ERROR(-20001,v_errm);

                ELSE

                    RAISE_APPLICATION_ERROR(-20000,v_errm);

                END IF;

            END;

        END IF;

      END LOOP;

END EXECUTE_TRANSACTION_26786;

ORA-26786 思想与 ORA-00001 思想类似, 不再赘述.

----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------

CREATE OR REPLACE PROCEDURE EXECUTE_TRANSACTION_26787(applyname IN VARCHAR2,ltxnid IN VARCHAR2) IS

 i      NUMBER;

  loopdog NUMBER;

  txnid  VARCHAR2(30);

  source VARCHAR2(128);

  msgno  NUMBER;

  msgcnt NUMBER;

  errno  NUMBER;

  errmsg VARCHAR2(2000);

  lcr    ANYDATA;

  rowlcr    SYS.LCR$_ROW_RECORD;

  typenm    VARCHAR2(61);

  res       NUMBER;

  command      VARCHAR2(10);

  old_values   SYS.LCR$_ROW_LIST;

  new_values   SYS.LCR$_ROW_LIST;

  v_code  NUMBER;

  v_errm  VARCHAR2(1024);

BEGIN

  SELECT LOCAL_TRANSACTION_ID,

         SOURCE_DATABASE,

         MESSAGE_NUMBER,

         MESSAGE_COUNT,

         ERROR_NUMBER,

         ERROR_MESSAGE

      INTO txnid, source, msgno, msgcnt, errno, errmsg

      FROM DBA_APPLY_ERROR

      WHERE LOCAL_TRANSACTION_ID =  ltxnid;

  DBMS_OUTPUT.PUT_LINE('--- Local Transaction ID: ' || txnid);

  DBMS_OUTPUT.PUT_LINE('--- Source Database: ' || source);

  DBMS_OUTPUT.PUT_LINE('---Error in Message: '|| msgno);

  DBMS_OUTPUT.PUT_LINE('---Error Number: '||errno);

  DBMS_OUTPUT.PUT_LINE('---Message Text: '||errmsg);

  i := msgno;

  loopdog :=0;

  WHILE i <= msgcnt  LOOP

      loopdog :=loopdog+1;

      DBMS_OUTPUT.PUT_LINE('--message: ' || i);

    lcr := DBMS_APPLY_ADM.GET_ERROR_MESSAGE(i, txnid); -- gets the LCR

    --print_lcr(lcr);

    typenm := lcr.GETTYPENAME();

    DBMS_OUTPUT.PUT_LINE('type name: ' || typenm);

    IF (typenm = 'SYS.LCR$_ROW_RECORD') THEN

        res := lcr.GETOBJECT(rowlcr);

        command := rowlcr.GET_COMMAND_TYPE();

        DBMS_OUTPUT.PUT_LINE('command type name: ' || command);

        IF command = 'DELETE' THEN

            -- Set the command_type in the row LCR to INSERT

            rowlcr.SET_COMMAND_TYPE('INSERT');

            old_values := rowlcr.GET_VALUES('old');

            -- Set the old values in the row LCR to the new values in the row LCR

            rowlcr.SET_VALUES('new', old_values);

            -- Set the old values in the row LCR to NULL

            rowlcr.SET_VALUES('old', NULL);

            -- Apply the row LCR as an INSERT into the hr.emp_del table

            rowlcr.EXECUTE(true);

        ELSIF command = 'UPDATE' THEN

            BEGIN

                old_values := rowlcr.GET_VALUES('old');

                new_values := rowlcr.GET_VALUES('new');

                rowlcr.EXECUTE(true);

                rowlcr.SET_VALUES('new', old_values);

                rowlcr.SET_VALUES('old', new_values);

                rowlcr.EXECUTE(true);

                EXCEPTION when OTHERS then

                    rowlcr.SET_COMMAND_TYPE('INSERT');

                    rowlcr.SET_VALUES('new', old_values);

                    -- Set the old values in the row LCR to NULL

                    rowlcr.SET_VALUES('old', NULL);

                    rowlcr.EXECUTE(true);

            END;

        END IF;

        BEGIN

            --dbms_apply_adm.execute_all_errors(applyname);

            dbms_apply_adm.execute_error(ltxnid);

            return;

            EXCEPTION when OTHERS then

                SELECT MESSAGE_NUMBER  INTO  i FROM DBA_APPLY_ERROR  WHERE LOCAL_TRANSACTION_ID =  ltxnid;

                v_code := SQLCODE;

                v_errm := SUBSTR(SQLERRM, 1, 1024);

                DBMS_OUTPUT.PUT_LINE('Error message: ' || v_errm);

                IF loopdog > msgcnt then

                    RAISE_APPLICATION_ERROR(-20002,'Insert or Delete error. please check your procedure.');

                ELSIF v_code = -26787 then

                    DBMS_OUTPUT.PUT_LINE('Error code(-26787): ' || v_code);

                    --null;

                ELSIF v_code = -26786 then

                    DBMS_OUTPUT.PUT_LINE('Error code(-26786): ' || v_code);

                    RAISE_APPLICATION_ERROR(-20786,v_errm);

                ELSIF v_code = -1 then

                    DBMS_OUTPUT.PUT_LINE('Error code(-1): ' || v_code);

                    RAISE_APPLICATION_ERROR(-20001,v_errm);

                ELSE

                    RAISE_APPLICATION_ERROR(-20001,v_errm);

                END IF;

        END;

    END IF;

  END LOOP;       

END EXECUTE_TRANSACTION_26787;

ORA-26787  处理方法相对简单, 因为数据不存在引起的, 只要把LCR 中old 字段插入即可.

参考 :

-- https://docs.oracle.com/cd/B28359_01/server.111/b28321/strms_apmon.htm

-- https://docs.oracle.com/cd/B10501_01/server.920/a96571/capappdemo.htm

-- https://docs.oracle.com/cd/B19306_01/appdev.102/b14258/t_lcr.htm#i997627

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