Question

我有一个Jsonb列，它存储元素数组，如下所示：

[ 
  {"id": "11", "name": "John", "age":"25", ..........}, 
  {"id": "22", "name": "Mike", "age":"35", ..........},
  {"id": "33", "name": "Tom",  "age":"45", ..........},
  .....
]

我想用一个全新的对象替换第二个对象（id = 22）。我不想一一更新每个属性，因为有许多属性，它们的值都可能已更改。我只想确定第二个元素并替换整个对象。

我知道有一个jsonb_set（）。但是，要更新第二个元素，我需要知道其数组索引= 1，以便可以执行以下操作：

jsonb_set(data, '{1}', '{"id": "22", "name": "Don", "age":"55"}',true)

但是我找不到任何搜索和获取该索引的方法。有人可以帮我吗？

Answer 1

我能想到的一种方法是结合row_number和json_array_elements：

-- test data
create table test (id integer, data jsonb);
insert into test values (1, '[{"id": "22", "name": "Don", "age":"55"}, {"id": "23", "name": "Don2", "age":"55"},{"id": "24", "name": "Don3", "age":"55"}]');
insert into test values (2, '[{"id": "32", "name": "Don", "age":"55"}, {"id": "33", "name": "Don2", "age":"55"},{"id": "34", "name": "Don3", "age":"55"}]');

select subrow, id, row_number() over (partition by id) 
from (
    select json_array_elements(data) as subrow, id 
    from test
) as t;
                  subrow                  | id | row_number
------------------------------------------+----+------------
 {"id": "22", "name": "Don", "age":"55"}  |  1 |          1
 {"id": "23", "name": "Don2", "age":"55"} |  1 |          2
 {"id": "24", "name": "Don3", "age":"55"} |  1 |          3
 {"id": "32", "name": "Don", "age":"55"}  |  2 |          1
 {"id": "33", "name": "Don2", "age":"55"} |  2 |          2
 {"id": "34", "name": "Don3", "age":"55"} |  2 |          3

-- apparently you can filter what you want from here
select subrow, id, row_number() over (partition by id) 
from (
    select json_array_elements(data) as subrow, id 
    from test
) as t
where subrow->>'id' = '23';

此外，请考虑您的架构设计。以这种方式存储数据可能不是最好的主意。

在Postgres中搜索和更新JSON数组元素

1 个答案: