如何 invoke/call 触发器内的序列

Question

我想自动增加我创建的 table id。此 table 将保存有关从我的数据库中的某个 table 所做的更改的日志。下面是我的代码和我得到的错误。请帮助我，并提前谢谢你。

create or replace Trigger PVFC_audit
after insert or delete or update on customer
for each row 
declare
v_user varchar2(20);
eventlog_id_go number;
v_date date;
v_time timestamp;
act_done varchar2(20) := case when updating then 'Update' when deleting then 'Delete' else 'Insert' end;
begin
IF eventlog_id IS NULL THEN  <--- eventlog_id is the actual column in my eventlogs table
SELECT eventlog_id_seq.NEXTVAL , user, To_Char(sysdate,'DD/MON/YYY'), To_char(CURRENT_TIMESTAMP,'HH12:MI:SS')
INTO eventlog_id_go, v_user, v_date, v_time from dual;
END IF;
if inserting then
    insert into eventlogs(eventlog_id, user_name, date_done, time_done, action_done, object_name)
    values (eventlog_id_go, v_user, v_date, v_time, act_done , 'customer');
elsif deleting then
    insert into eventlogs(eventlog_id, user_name, date_done, time_done, action_done, object_name)
    values (eventlog_id_go, v_user, v_date, v_time, act_done,'customer');
elsif updating then
    insert into eventlogs(eventlog_id, user_name, date_done, time_done, action_done, object_name)
    values (eventlog_id_go, v_user, v_date, v_time, act_done ,'customer');
end if;
end;

-----下面是我创建的序列-----

CREATE SEQUENCE  "SYSTEM"."EVENTLOG_ID_SEQ"  
MINVALUE 1 
MAXVALUE 9999999999999999999999999999 
INCREMENT BY 1 
START WITH 1 
CACHE 20 
NOORDER  
NOCYCLE ;

错误 (13,4)：PLS-00201：必须声明标识符 'EVENTLOG_ID'

Answer 1

你需要参考 pseudorecords old/new 值

IF :OLD.eventlog_id IS NULL THEN

或

IF :NEW.eventlog_id IS NULL THEN

Answer 2

eventlog_id is a column from another table named eventlogs

所以您不能在触发器中引用它：触发器只能看到拥有它的 table 的列。解决方案只是填充 INSERT 语句中的 eventlog_id 列。

顺便说一下，您的触发器有很多重复项。您可以极大地简化：

create or replace Trigger PVFC_audit
after insert or delete or update on customer
for each row 
declare
    act_done varchar2(20) := case when updating then 'Update' when deleting then 'Delete' else 'Insert' end;
begin

    if inserting then
        act_done := 'INSERT';
    elsif deleting then
        act_done := 'DELETE';
    elsif updating then
        act_done := 'UPDATE';
    end if;
    insert into eventlogs(eventlog_id, user_name, date_done, time_done, action_done, object_name)
    values (eventlog_id_seq.NEXTVAL , user, To_Char(sysdate,'DD/MON/YYY'), To_char(CURRENT_TIMESTAMP,'HH12:MI:SS')
    , act_done ,'customer');

end;

不确定为什么要将 date_done 和 time_done 填充为字符串。使用正确的数据类型会更有意义。

    insert into eventlogs(eventlog_id, user_name, date_done, time_done, action_done, object_name)
    values (eventlog_id_seq.NEXTVAL , user, trunc(sysdate), CURRENT_TIMESTAMP
    , act_done ,'customer');

如果 EVENTLOGS 将这些列定义为 VARCHAR2，那么这几乎肯定是一个数据模型错误，在某些时候会让您感到痛苦。

如何 invoke/call 触发器内的序列

How to invoke/call a sequence inside a trigger

sql

oracle

database-trigger