sequelize 中的递归 PostgreSQL 查询？

Question

Here我找到了一个递归查询的例子，它获取一个经理的所有下属：

这里是一个table测试数据：

INSERT INTO employees (
    employee_id,
    full_name,
    manager_id
)
VALUES
    (1, 'Michael North', NULL),
    (2, 'Megan Berry', 1),
    (3, 'Sarah Berry', 1),
    (4, 'Zoe Black', 1),
    (5, 'Tim James', 1),
    (6, 'Bella Tucker', 2),
    (7, 'Ryan Metcalfe', 2),
    (8, 'Max Mills', 2),
    (9, 'Benjamin Glover', 2),
    (10, 'Carolyn Henderson', 3),
    (11, 'Nicola Kelly', 3),
    (12, 'Alexandra Climo', 3),
    (13, 'Dominic King', 3),
    (14, 'Leonard Gray', 4),
    (15, 'Eric Rampling', 4),
    (16, 'Piers Paige', 7),
    (17, 'Ryan Henderson', 7),
    (18, 'Frank Tucker', 8),
    (19, 'Nathan Ferguson', 8),
    (20, 'Kevin Rampling', 8);

这是一个递归获取 id = 2 的经理的所有下属的查询。

WITH RECURSIVE subordinates AS (
    SELECT
        employee_id,
        manager_id,
        full_name
    FROM
        employees
    WHERE
        employee_id = 2
    UNION
        SELECT
            e.employee_id,
            e.manager_id,
            e.full_name
        FROM
            employees e
        INNER JOIN subordinates s ON s.employee_id = e.manager_id
) SELECT
    *
FROM
    subordinates;

有没有办法通过合理数量的 raw sql 插入来实现它？

Answer 1

Sequelize 不打算使用模型执行复杂的聚合或递归查询，因此您最终会 sequelize.query 执行这样的查询：

const subordinates = await sequelize.query('
WITH RECURSIVE subordinates AS (
    SELECT
        employee_id,
        manager_id,
        full_name
    FROM
        employees
    WHERE
        employee_id = $employee_id
    UNION
        SELECT
            e.employee_id,
            e.manager_id,
            e.full_name
        FROM
            employees e
        INNER JOIN subordinates s ON s.employee_id = e.manager_id
) SELECT
    *
FROM
    subordinates;', {
  type: QueryTypes.SELECT,
  bind: {
    employee_id: 2
  }
})

尽量不要将字符串连接到结果中 SQL 以避免 SQL 注入，并始终尝试使用 bind 或 replacements 选项来替换所需的值。

见raw queries

sequelize 中的递归 PostgreSQL 查询？

Recursive PostgreSQL query in sequelize?

sequelize.js