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在 Flink SQL 中构建一个 JSON_Object 值

[英]Build a JSON_Object value in Flink SQL

I have a Flink Table for which I want to write a select query that will return a JSON Object based on some fields.我有一个 Flink 表,我想为其编写一个 select 查询,该查询将基于某些字段返回 JSON Object。

Here is the query I want to do (based on calcite syntax: https://calcite.apache.org/docs/reference.html#constructor-functions ):这是我想做的查询(基于方解石语法: https://calcite.apache.org/docs/reference.html#constructor-functions ):

SELECT 
    myIdField,
    aFloatField,
    JSON_OBJECT('aFieldName':aFloatField)
FROM myTable

But when I try to use this query with Flink, I get the following error:但是当我尝试将此查询与 Flink 一起使用时,我收到以下错误:

org.apache.flink.table.api.ValidationException: SQL validation failed. No match found for function signature JSON_OBJECT(<null>, , )

What is the good way to do so?这样做的好方法是什么? I can't find anything about this in Flink documentation.我在 Flink 文档中找不到任何关于此的内容。

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