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將Group By與JSON_TABLE一起使用時Oracle中的異常行為

[英]Unexpected behavior in Oracle when using Group By with JSON_TABLE

我有一個非規格化的VIEW我們將其稱為VIEW_X ,它看起來像下面的樣子(它只是一個普通的簡單視圖-未實現或類似的東西):

ID   GROUP_ID   PART_1_ID                               PART_2_ID
1    1723189    cd69f0f4-a5ed-4196-916d-401e98ffec75    X1
1    1723189    cd69f0f4-a5ed-4196-916d-401e98ffec75    X2
2    1723185    8d5132cb-1b6e-4e79-9698-fd1962eb808f    K1
2    1723188    a191cb01-32ac-4ab4-bd6b-3ef777e395ca    K1

它被規范化了,因為它實際上代表了這樣的結構:

{
  id: 1,
  group_id: 1723189,
  part_1_id: 'cd69f0f4-a5ed-4196-916d-401e98ffec75'
  part_2_ids: ["X1", "X2"]
}

此視圖中的PART_2_ID是從JSON_TABLE中選擇的結果,原始表中的數據存儲在JSON_TABLE中,該原始數據存儲在類似["X1", "X2"]的數組中:

JSON_TABLE(a.PART_2_IDS, '$' COLUMNS (
            NESTED PATH '$[*]'
              COLUMNS (
                  PART_2_ID  VARCHAR2(4000) PATH '$'
                )
            )) p2

當我在此視圖上運行這樣的查詢時,盡管預期結果是ID2的單個結果,但得到0個結果:

SELECT ID
FROM VIEW_X
WHERE PART_2_ID IN ('K1')
GROUP BY ID
HAVING COUNT(DISTINCT(PART_2_ID)) = 1

ID
--
(no results)

圖1

奇怪的是,如果我只運行下面我得到預期的兩個結果,因為有兩行與ID 2那里是上一場比賽PART_2_IDK1

SELECT ID
FROM VIEW_X
WHERE PART_2_ID IN ('K1')

ID
--
 2
 2

但是,如果我運行以下兩個查詢之一,則ID 1

SELECT ID
FROM VIEW_X
WHERE PART_2_ID IN ('X1')
GROUP BY ID
HAVING COUNT(DISTINCT(PART_2_ID)) = 1

ID
--
 1

SELECT ID
FROM VIEW_X
WHERE PART_2_ID IN ('X1', 'X2')
GROUP BY ID
HAVING COUNT(DISTINCT(PART_2_ID)) = 2

ID
--
 1

我不明白為什么圖1沒有返回預期的結果-我有什么要忽略的嗎? 這是JSON_TABLE工作方式的怪癖嗎?

我不能在:

  • Oracle Database 12c Enterprise Edition Release 12.1.0.2.0 - 64bit Production 要么
  • Oracle Database 18c Enterprise Edition Release 18.0.0.0.0 - Productionhttps://livesql.oracle.com

Oracle安裝程序

CREATE TABLE table1 ( document CLOB CONSTRAINT ensure_json CHECK (document IS JSON) );

INSERT INTO table1 ( document ) VALUES ( '{"id":1,"group_id":1723189,"part_1_id":"cd69f0f4-a5ed-4196-916d-401e98ffec75","part_2_ids":["X1","X2"]}' );
INSERT INTO table1 ( document ) VALUES ( '{"id":2,"group_id":1723185,"part_1_id":"8d5132cb-1b6e-4e79-9698-fd1962eb808f","part_2_ids":["K1"]}' );
INSERT INTO table1 ( document ) VALUES ( '{"id":2,"group_id":1723188,"part_1_id":"a191cb01-32ac-4ab4-bd6b-3ef777e395ca","part_2_ids":["K1"]}' );

CREATE VIEW VIEW_X AS
SELECT p.*
FROM   table1 t
       CROSS JOIN
       JSON_TABLE(
         t.document,
         '$'
         COLUMNS (
           id        PATH '$.id',
           group_id  PATH '$.group_id',
           part_1_id PATH '$.part_1_id',
           NESTED PATH '$.part_2_ids[*]'
             COLUMNS (
               PART_2_ID  VARCHAR2(4000) PATH '$'
             )
           )
         ) p;

查詢1

SELECT *
FROM   VIEW_X;

結果

        ID   GROUP_ID PART_1_ID                            PART_2_ID
---------- ---------- ------------------------------------ ---------
         1    1723189 cd69f0f4-a5ed-4196-916d-401e98ffec75 X1   
         1    1723189 cd69f0f4-a5ed-4196-916d-401e98ffec75 X2   
         2    1723185 8d5132cb-1b6e-4e79-9698-fd1962eb808f K1   
         2    1723188 a191cb01-32ac-4ab4-bd6b-3ef777e395ca K1   

查詢2

SELECT ID
FROM VIEW_X
WHERE PART_2_ID IN ('K1')
GROUP BY ID
HAVING COUNT(DISTINCT(PART_2_ID)) = 1;

結果

ID
--
 2

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