我有一张桌子
Visitor: (id, signup_up, sessions, email, custom_fields)
其中custom_fields是格式为
CustomField: ( field, value )示例：(domain, www.somedomain.com)
我想在signed_up, sessions, email数组中取CustomField列及其值和custom_fields json对象，并将它们合并到名为data的第3个字段中相同的CustomField结构，即。每个条目的格式为field: value。
实施例
给定这些行
id | sessions | email | custom_fields
---------------------------------------------------------------
1 | 3 | test@gmail.com [{ field: domain, value: "www.hello.com" }, { field: type, value: "Customer" }]
---------------------------------------------------------------
2 | 5 | another@gmail.com [{ field: domain, value: "www.other.com" }, { field: type, value: "Customer" }]
我想得到
id | fields
-----------------------
1 | [{sessions: 3, email: test@gmail.com, domain: "www.hello.com", type: "Customer"}]
----------------------
2 | [{sessions: 5, email: another@gmail.com, domain: "www.other.com", type: "Customer"}]
关于如何实现这一点的任何想法？
非常感谢任何帮助
答案 0 :(得分：5)
示例数据（这应该是问题的一部分，而不是答案;请注意正确的json语法）：
show/hide function提示1.使用$('#searchField').keyup(function(){
var valThis = $(this).val().toLowerCase();
$('.thumbnail')
.hide() // reset display val of .thumbnail
.filter(function(){ // get items with search-text only
var pTxt = $('p',this).text().toLowerCase();
return ( pTxt.indexOf(valThis) != -1 ) ? this : '' ;
})
.show('fast'); // show items with search-text
});
并在create table visitor (id int, sessions int, email text, custom_fields jsonb);
insert into visitor values
(1, 3, 'test@gmail.com', '[{"field": "domain", "value": "www.hello.com" }, {"field": "type", "value": "Customer"}]'),
(2, 5, 'another@gmail.com', '[{"field": "domain", "value": "www.other.com" }, {"field": "type", "value": "Customer"}]');
和jsonb_array_elements()列中选择field和value的json值：
key提示2.使用value将这些对（select id, sessions, email, elem->>'field' as key, elem->>'value' as value
from visitor, jsonb_array_elements(custom_fields) elem;
id | sessions | email | key | value
----+----------+-------------------+--------+---------------
1 | 3 | test@gmail.com | domain | www.hello.com
1 | 3 | test@gmail.com | type | Customer
2 | 5 | another@gmail.com | domain | www.other.com
2 | 5 | another@gmail.com | type | Customer
(4 rows)
）聚合到json对象中：
jsonb_object_agg()最终查询。添加（连接）从列key, value和select
id,
jsonb_object_agg(key, value)
from (
select id, sessions, email, elem->>'field' as key, elem->>'value' as value
from visitor, jsonb_array_elements(custom_fields) elem
) s
group by id, sessions, email
order by id;
id | jsonb_object_agg
----+-------------------------------------------------
1 | {"type": "Customer", "domain": "www.hello.com"}
2 | {"type": "Customer", "domain": "www.other.com"}
(2 rows)
构建的json对象，并使用所有对象构建一个json数组：
session还有一个提示（或技巧）：
email