我有一张桌子:
当我从表中选择所有内容时:
SELECT JSON_VALUE(LastReadings, '$.lastReadings."7-temp".value') as x FROM
(VALUES
(2,N'{"groups": [],"lastReadings": {"amir": {"name": "Ink","value":12.0},"7-temp": {"name": "Temperature","value":12}},"customId":null}'),
(3,N'{"groups": [],"lastReadings": {"amir": {"name": "Ink","value":12.0},"7-temp": {"name": "Temperature","value":32}},"customId":null}'),
(4,N'{"groups": [],"lastReadings": {"amir": {"name": "Ink","value":12.0},"7-temp": {"name": "Temperature","value":22}},"customId": null}'),
(5,N'{"groups": [],"lastReadings": {"amir": {"name": "Ink","value": 12.0},"7-temp": {"name": "Temperature","value":123}},"customId": null}')
)
[AmirTestTable](Id,LastReadings )
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我得到
+-----+
| x |
+-----+
| 12 |
| 32 |
| 22 |
| 123 |
+-----+
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但是,当我尝试添加 where 子句时:
SELECT JSON_VALUE(LastReadings, '$.lastReadings."7-temp".value') as x
FROM
(VALUES
(2,N'{"groups": [],"lastReadings": {"amir": {"name": "Ink","value":12.0},"7-temp": {"name": "Temperature","value":12}},"customId":null}'),
(3,N'{"groups": …Run Code Online (Sandbox Code Playgroud)