过程PLSQL中的2个合并语句

我试图在过程中使用两个合并语句。 其中一个表应该删除不在另一个表中的行

另一个应该插入表中没有的

在这种情况下，我得到的错误是缺少一个关键字

create or replace noneditionable procedure merge_test
as
BEGIN

Execute immediate 'alter table
   table person
DISABLE constraint
FK_FGH_ID ';


Merge into (select distinct * from 
person_test) t1
Using (select * from person) p1
On (p1.person_id = t1.person_id)
When not matched then
DELETE
FROM
    person
WHERE
    Person_id = p1.person_id;
COMMIT;

Merge into person p
USING (select distinct * from 
person_test) t
On (t.person_id = p.person_id)
When not matched then
Insert(person_id,vorname, nachname, mobil, telefon, fax, e_mail, fgh_id)
values(t.person_id, t.vorname, t.nachname, t.mobil, t.telefon, t.fax, t.e_mail, t.fgh_id);
COMMIT;

Execute immediate 'alter table
   person
ENABLE constraint
   FK_FGH_ID ';


End merge_test;

关键字丢失错误位于第一次合并中的“不匹配时”。

---

另一个问题是，在一个过程中是否可能有两个Merge语句。

是的，在一个过程中有两个

Merge

语句是绝对可能的，但是为什么在这种情况下使用它们呢？只需使用一个简单的

DELETE

语句，然后使用类似于下面的

INSERT

语句

CREATE OR REPLACE NONEDITIONABLE PROCEDURE merge_test
AS
BEGIN
    EXECUTE IMMEDIATE 'alter table person DISABLE constraint FK_FGH_ID';

    DELETE FROM person
          WHERE person_id NOT IN (SELECT person_id FROM person_test);

    INSERT INTO person (person_id,
                        vorname,
                        nachname,
                        mobil,
                        telefon,
                        fax,
                        e_mail,
                        fgh_id)
        SELECT person_id,
               vorname,
               nachname,
               mobil,
               telefon,
               fax,
               e_mail,
               fgh_id
          FROM person_test
         WHERE person_id NOT IN (SELECT person_id FROM person);

    EXECUTE IMMEDIATE 'alter table person ENABLE constraint FK_FGH_ID';
END merge_test;

---

在存储过程中使用多个

MERGE

语句不是问题

通过转换相关部分，仍然可以使用第一个

MERGE

语句

WHEN NOT MATCHED THEN
DELETE FROM person
WHERE Person_id = p1.person_id

致：

但是

DELETE

语句在

之后不匹配时不能发生

顺便说一句，在一个事务中两个有多个
COMMIT
，而不是只保留最后一个，这不是一个好的做法。
类似这样的事情：

create or replace noneditionable procedure merge_test
IS

BEGIN

    Execute immediate 'alter table person DISABLE constraint FK_FGH_ID ';

    Merge into person_test t1
    Using (select * from person) p1
    On (t1.person_id = p1.person_id)
    when matched then 
         update set t1.Person_id = t1.Person_id
             where t1.Person_id = p1.person_id
         delete 
             where t1.Person_id = p1.person_id;

    COMMIT;
    
    Merge into person p
    USING (select * from person_test) t
    On (t.person_id = p.person_id)
    When not matched then
        Insert(person_id,vorname, nachname, mobil, telefon, fax, e_mail, fgh_id)
        values(t.person_id, t.vorname, t.nachname, t.mobil, t.telefon, t.fax, t.e_mail, t.fgh_id);
    
    COMMIT;
    
    Execute immediate 'alter table person ENABLE constraint FK_FGH_ID ';

End merge_test;
/

请注意，您的第一个Execute immediate语句中有一个错误。应该是：

Execute immediate 'alter table person DISABLE constraint FK_FGH_ID ';

你应该绝对避免这种可怕的“
select*
”行为。用显式列名替换它。MERGE语句中的DELETE仅适用于合并表，也就是说，我们只能从WHEN MATCHED分支调用它。整个第一个合并语句完全错误。当搜索者从
person\u test
查询时，使用DISTINCT。假设他们有这样做的正当理由，你应该把它包括在你的插入。。。SELECT语句。
Execute immediate 'alter table person DISABLE constraint FK_FGH_ID ';