加入 2 个表并使用 mysql 显示一列的总和

Question

我有 2 个包含项目数据和付款的表格。每个项目可能有多个付款行。 表 1：项目

  id project_name
  1 Test Project
  2 Test Project 2

还有表 2：project_payments

id project_id payment_amount
1       1          100
2       1          200
3       1          100
4       2          150
5       2          200

我需要获取以下格式的数据

project_id payment_id payment amount  total_received
     1          1           100           400
     1          2           200           400
     1          3           100           400
     2          4           150           350
     2          5           200           350  

    

即通过每个project_id的支付金额之和得到total_received

我已经写了以下

SELECT projects.id as project_id, 
           projects.*, 
           project_payments.*, 
           sum(project_payments.payment_amount) 
FROM projects 
JOIN project_payments on projects.id = project_payments.project_id

但它只从每个项目返回一行。我怎样才能得到上述数据。

Answer 1

SELECT projects.*, 
       project_payments.*, 
       SUM(project_payments.payment_amount) OVER (PARTITION BY projects.id) total_received
FROM projects
JOIN project_payments ON projects.id = project_payments.project_id

https://dbfiddle.uk/?rdbms=mariadb_10.3&rdbms2=mysql_8.0&fiddle=0ed87c2ac05f20097c1272458ecd6e41

PS。需要 MySQL 8+ 或 MariaDB 10.2+。