给定了一个JSONB和一组键
我已经尝试提取键值并分配给文本[],然后使用jsonb_object(text [](。它运行良好,但是问题到了,当键带有一系列JSON时。
create table my_jsonb_table
(
data_col jsonb
);
insert into my_jsonb_table (data_col) Values ('{
"schemaVersion": "1",
"Id": "20180601550002",
"Domains": [
{
"UID": "29aa2923",
"quantity": 1,
"item": "book",
"DepartmentDomain": {
"type": "paper",
"departId": "10"
},
"PriceDomain": {
"Price": 79.00,
"taxA": 6.500,
"discount": 0
}
},
{
"UID": "bbaa2923",
"quantity": 2,
"item": "pencil",
"DepartmentDomain": {
"type": "wood",
"departId": "11"
},
"PriceDomain": {
"Price": 7.00,
"taxA": 1.5175,
"discount": 1
}
}
],
"finalPrice": {
"totalTax": 13.50,
"total": 85.0
},
"MetaData": {
"shopId": "1405596346",
"locId": "95014",
"countryId": "USA",
"regId": "255",
"Date": "20180601"
}
}
')
这是我要实现的目标:
SELECT some_magic_fun(data_col,'Id,Domains.UID,Domains.DepartmentDomain.departId,finalPrice.total')::jsonb FROM my_jsonb_table;
我正在尝试创建该魔术功能,该功能以JSONB格式提取给定的键,到目前为止,我能够提取标量项目并将其放入文本[]并使用JSONB_OBJECT中。但是不知道如何提取数组的所有元素
预期输出:
{
"Id": "20180601550002",
"Domains": [
{
"UID": "29aa2923",
"DepartmentDomain": {
"departId": "10"
}
},
{
"UID": "bbaa2923",
"DepartmentDomain": {
"departId": "11"
}
}
],
"finalPrice": {
"total": 85.0
}
}
我不知道任何魔术。您必须自己重建。
select jsonb_build_object(
-- Straight forward
'Id', data_col->'Id',
'Domains', (
-- Aggregate all the "rows" back together into an array.
select jsonb_agg(
-- Turn each array element into a new object
jsonb_build_object(
'UID', domain->'UID',
'DepartmentDomain', jsonb_build_object(
'departId', domain#>'{DepartmentDomain,departId}'
)
)
)
-- Turn each element of the Domains array into a row
from jsonb_array_elements( data_col->'Domains' ) d(domain)
),
-- Also pretty straightforward
'finalPrice', jsonb_build_object(
'total', data_col#>'{finalPrice,total}'
)
) from my_jsonb_table;
这可能不是JSON列的好使用。您的数据是关系的,可以更好地符合传统的关系表。