我有一个简单的数据库结构,具有一对多的关系
CREATE TABLE customer (
id SERIAL PRIMARY KEY,
email TEXT,
first_name TEXT,
last_name TEXT
);
CREATE TABLE customer_address (
id SERIAL PRIMARY KEY,
customer_id INTEGER NOT NULL,
street_name TEXT NOT NULL,
street_number TEXT NOT NULL,
zip_code TEXT NOT NULL,
city TEXT NOT NULL
);
对于我的应用程序,我想将每个客户的所有地址作为一行返回,我将所有地址封装在json数组中。这样做是这样的:
SELECT customer.*,
addresses
FROM customer
left join (SELECT
Array_to_json(Array_agg(
Json_build_object('id', address.id, 'street_name', address.street_name, 'street_number', address.street_number, 'zip_code', address.zip_code, 'city', address.city))) AS addresses,
address.customer_id
AS customer_id
FROM customer_address AS address
GROUP BY address.customer_id) addresses
ON addresses.customer_id = customer.id
join customer_address
ON customer_address.customer_id = customer.id
这样可以正常工作,并为每个结果提供一个结果集,其中包含一个名为addresses
的元素,其中包含所有客户地址的JSON数组。
现在我想选择所有客户(包括他们所有的地址),其street_name
就像某个搜索词。我无法让它发挥作用。当一个地址的街道名称包含某个值(与ILIKE
匹配)时,如何选择包括所有内联地址的完整记录?
我尝试添加:WHERE customer_address.street_name LIKE 'Ro'
,虽然这有效,但如果我用完全不同的东西替换这个where语句,例如WHERE customer.id > 0
,我在结果集中得到双打
这是一个sql小提琴玩:
此连接条件看起来错误:
JOIN customer_address ON customer_address.id = customer.id
不应该
JOIN customer_address ON customer_address.customer_id = customer.id
这是小提琴:http://sqlfiddle.com/#!17/2fff0/6
在对原始答案进行讨论之后,这是解决问题的最终解决方案:
这是否涵盖了您的预期结果?
SELECT customer.*,addresses FROM customer LEFT JOIN (SELECT array_to_json(array_agg(json_build_object('id',address.id,'street_name',address.street_name,'street_number',address.street_number,'zip_code',address.zip_code,'city',address.city))) AS addresses,address.customer_id AS customer_id FROM customer_address AS address GROUP BY address.customer_id) addresses ON addresses.customer_id = customer.id JOIN customer_address ON customer_address.id = customer.id WHERE customer_address.street_name LIKE 'Ro%'
id | email | first_name | last_name | addresses -: | :------------ | :--------- | :-------- | :----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- 1 | [email protected] | John | Doe | [{"id" : 1, "street_name" : "Route", "street_number" : "222", "zip_code" : "9000", "city" : "NY"},{"id" : 2, "street_name" : "Ro", "street_number" : "444", "zip_code" : "9000", "city" : "LA"}]
dbfiddle here