Postgresql 从 JSONB 字段中的对象数组中获取键

Question

这里是 jsonb 列的虚拟数据

[ { "name": [ "sun11", "sun12" ], "alignment": "center", "more": "fields" }, { "name": [ "sun12", "sun13" ], "alignment": "center" }, { "name": [ "sun14", "sun15" ] }]

我想从 jsonb 个对象数组中获取所有名称键值...期待输出 -

[ [ "sun11", "sun12" ], [ "sun12", "sun13" ], [ "sun14", "sun15" ] ]

问题是我可以通过给出 0、1 等索引来获取名称键值

SELECT data->0->'name' FROM public."user";
[ "sun11", "sun12" ]

但我无法从 object.I 的同一个数组中获取所有名称键值只想从 json 对象数组中获取所有键值。任何帮助都会有所帮助。谢谢

Answer 1

demo:db<>fiddle（首先进行最终查询，下面是中间步骤）

WITH data AS (
    SELECT '[ { "name": [ "sun11", "sun12" ], "alignment": "center", "more": "fields" }, { "name": [ "sun12", "sun13" ], "alignment": "center" }, { "name": [ "sun14", "sun15" ] }]'::jsonb AS jsondata
)
SELECT 
    jsonb_agg(elems.value -> 'name')    -- 2
FROM 
    data,
    jsonb_array_elements(jsondata) AS elems -- 1

jsonb_array_elements() 将每个数组元素扩展为一行
->运算符给出属性名数组；之后 jsonb_agg() 将所有提取的数组再次放入一个数组中。

Answer 2

我的例子

SELECT DISTINCT sub.name FROM (

SELECT
jsonb_build_object('name', p.data->'name') AS name
FROM user AS u
WHERE u.data IS NOT NULL
) sub
WHERE sub.name != '{"name": null}';

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