Postgresql 如何从带有postgres的子查询中获取关联行数组
我是postgres的新手,在我从mySQL跨越之前尝试了一些东西 我要做的是把一个关联数组放到一个查询中。 它与用户有关,用户可以选择多种联系人类型,如电话、电子邮件和Facebook,我想在“联系人”栏中检索这些联系人 对于可视化:Postgresql 如何从带有postgres的子查询中获取关联行数组,postgresql,database-design,subquery,Postgresql,Database Design,Subquery,我是postgres的新手,在我从mySQL跨越之前尝试了一些东西 我要做的是把一个关联数组放到一个查询中。 它与用户有关,用户可以选择多种联系人类型,如电话、电子邮件和Facebook,我想在“联系人”栏中检索这些联系人 对于可视化: { "first_name": "This", "last_name": "is me", "likes": [], "city": null } 我想得到这样的东西: { "first_name": "This", "last_name": "Is me",
{
"first_name": "This",
"last_name": "is me",
"likes": [],
"city": null
}
我想得到这样的东西:
{
"first_name": "This",
"last_name": "Is me",
"likes": [],
"city": null,
"contact":
[
{"type":1, "value":"myemail@gmail.com", "privacy_rule":1},
{"type":4, "value":"myfacebook", "privacy_rule":1},
{"type":9, "value":"mylinkedin", "privacy_rule":1}
]
}
因此,主要问题是:
SELECT u.first_name, u.last_name, u.about, ARRAY(SELECT like_id FROM users_likes l WHERE l.user_id = u.user_id), u.city FROM users u WHERE user_id = {id}
SELECT c.type, c.value, c.privacy_rule FROM users_contact c WHERE c.user_id = u.user_id
子查询将是:
SELECT u.first_name, u.last_name, u.about, ARRAY(SELECT like_id FROM users_likes l WHERE l.user_id = u.user_id), u.city FROM users u WHERE user_id = {id}
SELECT c.type, c.value, c.privacy_rule FROM users_contact c WHERE c.user_id = u.user_id
但是如何将其集成到主查询中以返回结果行数组呢?
有可能吗
提前谢谢
罗恩啊,再多说几句,下面是答案。 使用json_构建_对象:
SELECT u.first_name, u.last_name,
ARRAY(SELECT like_id FROM users_likes l WHERE l.user_id = u.user_id) as likes,
ARRAY(SELECT json_build_object("contact_id", c.contact_id,
"value", c.value, "privacy",c.privacy)
FROM users_contact c WHERE c.user_id = u.user_id) as contact
FROM users_basic u WHERE user_id = {id}
这使得:
"first_name": "This",
"last_name": "Is Me",
"about": null,
"likes": [],
"city": null,
"contact": [
{
"contact_id": 1,
"value": "bbla",
"privacy": 2,
"type": "Phone"
},
{
"contact_id": 3,
"value": "blabla",
"privacy": 2,
"type": "Company Email"
},
{
"contact_id": 4,
"value": "blablabla",
"privacy": 2,
"type": "Telegram Id"
}
]
希望它能帮助别人