在Oracle视图中的JSON列上使用点表示法

我试图弄清楚如何将JSON列从表中拉入视图，并且仍然能够在

WHERE

子句中使用点表示法

我目前已经正确定义了列，并且可以在直接命中表的查询中的

WHERE

子句中使用点表示法。我遇到的问题是，该表当前在一个视图中使用，我需要使用该视图返回所有相关数据

如果我只是在视图定义中包含列，我将失去使用点表示法在字符串中搜索值的能力

如果我在从视图检索数据的查询中将视图连接回这个表，我就能够在

where

子句中使用点表示法，但是，我会受到巨大的性能影响（慢4-5倍）

下面是存储在每一行中的JSON示例

{"fields": 
  {
    "field1":{ "name": "field1","label": "My Field 1","value": "ABCD"},
    "field2":{ "name": "field2","label": "My Field 2","value": ""},
    "field3":{ "name": "field3","label": "My Field 3","value": "XYZ"},
    "field4":{ "name": "field4","label": "My Field 4","value": ""},
    "field5":{ "name": "field5","label": "My Field 5","value": ""},
    "field6":{ "name": "field6","label": "My Field 6","value": "Y"},
    "field7":{ "name": "field7","label": "My Field 7","value": ""}
  }
}

我希望能够在视图中执行的操作是

其中json\u col\u name.fields.field1.value='ABCD'

请记住，对象键（如

field1

、

field2

）将是任意值，不总是遵循命名约定，也不总是有7个字段

我并没有和这个模式结过婚，我很乐意改变它，让它发挥作用

下面是重现表/视图和数据的SQL语句

create table MAIN_TABLE
(
    ID NUMBER(10) not null
        constraint MY_PK
            primary key,

    JSON_DATA CLOB
        constraint JSON_DATA_CONST
            check (JSON_DATA IS JSON)
)

INSERT INTO MAIN_TABLE (ID, JSON_DATA) VALUES (1, '{"fields": {"field1":{ "name": "field1","label": "My Field 1","value": "ABCD"},"field2":{ "name": "field2","label": "My Field 2","value": "XYZ"},"field3":{ "name": "field3","label": "My Field 3","value": "Y"},"field4":{ "name": "field4","label": "My Field 4","value": ""},"field5":{ "name": "field5","label": "My Field 5","value": ""},"field6":{ "name": "field6","label": "My Field 6","value": ""},"field7":{ "name": "field7","label": "My Field 7","value": ""},}}');

INSERT INTO MAIN_TABLE (ID, JSON_DATA) VALUES (2, '{"fields": {"field1":{ "name": "field1","label": "My Field 1","value": ""},"field2":{ "name": "field2","label": "My Field 2","value": "XYZ"},"field3":{ "name": "field3","label": "My Field 3","value": "Y"},"field4":{ "name": "field4","label": "My Field 4","value": "QWERTY"},"field5":{ "name": "field5","label": "My Field 5","value": ""},"field6":{ "name": "field6","label": "My Field 6","value": ""},"field7":{ "name": "field7","label": "My Field 7","value": ""},}}');

create or replace view JSON_TEST_VIEW as
select id, JSON_DATA
from MAIN_TABLE
union all
select id, JSON_DATA from MAIN_TABLE;

这个命中表的查询按预期工作

select * from MAIN_TABLE m where m.json_data.fields.field1.value='ABCD'

此查询命中视图，抛出一个

无效标识符

错误

select * from JSON_TEST_VIEW jtv where jtv.JSON_DATA.fields.field1.value='ABCD'

---

我相当确定问题源于

UNION

，因为我最初在我的repo案例中看到问题时没有添加它（原始视图具有

UNION

）

点表示法仅对标记了“is-JSON”检查约束的JSON有效

在您的表中，我们知道数据是JSON，但一旦您将其放入视图中，我们就不再有这种信心。毕竟你本可以做的

create view V as
select [some json]
union all
select [some junk]

因此，在本例中，您需要让我们知道JSON确实可以这样处理

SQL> create or replace view JSON_TEST_VIEW as
  2  select m.id,  treat(m.json_data as json) JSON_DATA
  3  from
  4  (
  5    select id, JSON_DATA
  6    from MAIN_TABLE
  7    union all
  8    select id, JSON_DATA from MAIN_TABLE
  9  ) m;

View created.

SQL>
SQL> select * from JSON_TEST_VIEW jtv where jtv.JSON_DATA.fields.field1.value='ABCD';

        ID JSON_DATA
---------- --------------------------------------------------------------------------------
         1 {"fields": {"field1":{ "name": "field1","label": "My Field 1","value": "ABCD"},"
           field2":{ "name": "field2","label": "My Field 2","value": "XYZ"},"field3":{ "nam
           e": "field3","label": "My Field 3","value": "Y"},"field4":{ "name": "field4","la
           bel": "My Field 4","value": ""},"field5":{ "name": "field5","label": "My Field 5
           ","value": ""},"field6":{ "name": "field6","label": "My Field 6","value": ""},"f
           ield7":{ "name": "field7","label": "My Field 7","value": ""},}}

         1 {"fields": {"field1":{ "name": "field1","label": "My Field 1","value": "ABCD"},"
           field2":{ "name": "field2","label": "My Field 2","value": "XYZ"},"field3":{ "nam
           e": "field3","label": "My Field 3","value": "Y"},"field4":{ "name": "field4","la
           bel": "My Field 4","value": ""},"field5":{ "name": "field5","label": "My Field 5
           ","value": ""},"field6":{ "name": "field6","label": "My Field 6","value": ""},"f
           ield7":{ "name": "field7","label": "My Field 7","value": ""},}}

---

点表示法仅对标记有“is JSON”检查约束的JSON有效

在您的表中，我们知道数据是JSON，但一旦您将其放入视图中，我们就不再有这种信心。毕竟你本可以做的

create view V as
select [some json]
union all
select [some junk]

因此，在本例中，您需要让我们知道JSON确实可以这样处理

SQL> create or replace view JSON_TEST_VIEW as
  2  select m.id,  treat(m.json_data as json) JSON_DATA
  3  from
  4  (
  5    select id, JSON_DATA
  6    from MAIN_TABLE
  7    union all
  8    select id, JSON_DATA from MAIN_TABLE
  9  ) m;

View created.

SQL>
SQL> select * from JSON_TEST_VIEW jtv where jtv.JSON_DATA.fields.field1.value='ABCD';

        ID JSON_DATA
---------- --------------------------------------------------------------------------------
         1 {"fields": {"field1":{ "name": "field1","label": "My Field 1","value": "ABCD"},"
           field2":{ "name": "field2","label": "My Field 2","value": "XYZ"},"field3":{ "nam
           e": "field3","label": "My Field 3","value": "Y"},"field4":{ "name": "field4","la
           bel": "My Field 4","value": ""},"field5":{ "name": "field5","label": "My Field 5
           ","value": ""},"field6":{ "name": "field6","label": "My Field 6","value": ""},"f
           ield7":{ "name": "field7","label": "My Field 7","value": ""},}}

         1 {"fields": {"field1":{ "name": "field1","label": "My Field 1","value": "ABCD"},"
           field2":{ "name": "field2","label": "My Field 2","value": "XYZ"},"field3":{ "nam
           e": "field3","label": "My Field 3","value": "Y"},"field4":{ "name": "field4","la
           bel": "My Field 4","value": ""},"field5":{ "name": "field5","label": "My Field 5
           ","value": ""},"field6":{ "name": "field6","label": "My Field 6","value": ""},"f
           ield7":{ "name": "field7","label": "My Field 7","value": ""},}}

---

请提供一个问题的最小可复制示例。您能给出一个针对表和视图使用的查询示例吗，除了表和视图的定义之外？我正在简化表和视图的定义。@pmdba我已经用必要的SQL更新了问题以重现问题。请提供一个最小的可重现问题的示例。您能给出一个您正在使用的查询的示例吗，表和视图以及表和视图的定义？我正在简化表和视图的定义。@pmdba我已使用必要的SQL更新了问题，以重现问题。