1

我有两张桌子：

CREATE TABLE
    test
    (
        id INTEGER,
        str VARCHAR2(10)
    );
CREATE TABLE
    test2
    (
        id INTEGER,
        tmp VARCHAR2(10)
    );

和内容：

INSERT INTO test2   (id,    tmp)    VALUES (    10,'tmp10');
INSERT INTO test2   (id,    tmp)    VALUES (    20,'tmp20');

当我运行下一个脚本时：

MERGE INTO  test mt
USING   (
        SELECT
            1  AS id,
            10 AS id2
        FROM
            dual) nr
ON  (   mt.id=nr.id)
WHEN MATCHED THEN
   UPDATE SET str=(SELECT   id  FROM test2  WHERE       id=nr.id2)
WHEN NOT MATCHED    THEN 
   INSERT   (id,str)    VALUES (    nr.id,(SELECT   tmp FROM    test2   WHERE   id=nr.id2) );

我看到错误：

[Error Code: 904, SQL State: 42000]  ORA-00904: "NR"."ID2": invalid identifier

但是当我跑步时：

MERGE INTO  test mt
USING   (
        SELECT
            1  AS id,
            10 AS id2
        FROM
            dual) nr
ON  (   mt.id=nr.id)
WHEN MATCHED THEN
   UPDATE SET str=(SELECT   id  FROM test2  WHERE       id=nr.id2)
WHEN NOT MATCHED    THEN 
   INSERT   (id,str)    VALUES (    nr.id,(SELECT   tmp FROM    test2   WHERE   id=10) );

有用。

为什么新记录上的链接在更新语句中有效，但在插入语句中无效？

4

1 回答 1

1

试试这个...注意对 MERGE 的更改...

1）在 USING 子句中，确保您有一个完整的查询，它返回您想要的结果..

2）您的 INSERT 将直接从那里引用该值..而不是来自 INSERT 子语句中的子查询..

  SQL> select * from test;

  no rows selected

  SQL> select * from test2;

          ID TMP
  ---------- ----------
          10 tmp10
          20 tmp20

  SQL> SELECT id, tmp
    2  FROM test2
    3   WHERE id IN ( 1, 10 )
    4  /

          ID TMP
  ---------- ----------
          10 tmp10

  SQL> MERGE INTO test mt
    2     USING (
    3        SELECT id, tmp
    4          FROM test2
    5         WHERE id IN ( 1, 10 )
    6         )  nr
    7     ON ( mt.id = nr.id )
    8     WHEN MATCHED THEN
    9        UPDATE set str = nr.tmp
   10     WHEN NOT MATCHED THEN
   11        INSERT ( id, str ) VALUES ( nr.id, nr.tmp )
   12  /

  1 row merged.

  SQL> commit;

  Commit complete.

  SQL> select * from test;

          ID STR
  ---------- ----------
          10 tmp10

  SQL>

或验证/测试 INSERT 部分：

  SQL> MERGE INTO test mt
    2     USING (
    3        SELECT id, tmp
    4          FROM test2
    5         WHERE id IN ( 1, 10, 20 )
    6         )  nr
    7     ON ( mt.id = nr.id )
    8     WHEN MATCHED THEN
    9        UPDATE set str = nr.tmp
   10     WHEN NOT MATCHED THEN
   11        INSERT ( id, str ) VALUES ( nr.id, nr.tmp )
   12  /

  2 rows merged.

  SQL> select * from test;

          ID STR
  ---------- ----------
          10 tmp10
          20 tmp20

  SQL>
于 2015-11-20T16:51:03.973 回答