Postgresql 用于多个DELETE语句的Postgres变量

我们有一些没有设置级联的表，但是我们想在删除项目时用一个命令手动清理它们

例如，要基于具有

标识符='abcdefg'

的项目删除

权限

表和

投票

表，我们首先要查找项目的

id

，然后使用该id删除相关表：

WITH proj_id AS (
  SELECT id FROM "Projects" WHERE identifier = 'abcdefg'
)

DELETE FROM "Permissions" WHERE project_id IN (proj_id);
DELETE FROM "Votes" WHERE project_id IN (proj_id);
DELETE FROM "Gadgets" WHERE project_id IN (proj_id);
...
DELETE FROM "Projects" WHERE id IN (proj_id);

这不起作用，但我认为它说明了目标

有没有一种方法可以跨多个表完成此删除，而无需多次写入

标识符
值？
将“Projects”删除移到WITH子句中，并将其返回proj_id列。然后用逗号分隔DELETE子句，使它们都成为公共表表达式的一部分

例如：

WITH proj_id AS (
  DELETE FROM "Projects"
  WHERE identifier = 'abcdefg'
  RETURNING id
),
perm_del AS (
  DELETE FROM "Permissions" p
  USING proj_id
  WHERE p.project_id = proj_id.id),
vote_del AS (
  DELETE FROM "Votes" v
  USING proj_id
  WHERE v.project_id = proj_id.id),
gadg_del AS (
  DELETE FROM "Gadgets" g
  USING proj_id
  WHERE g.project_id = proj_id.id),
...
SELECT id AS deleted
FROM proj_id;

我在“RETURNING”
处或附近得到
语法错误，如果我删除该行（和省略号），我在
SELECT id AS deleted处或附近得到
语法错误
看起来我忽略了将该语句转换为delete。我现在已经更新了。谢谢你的更新；仍在获取第二个错误
error:syntax error位于或接近“SELECT”
第18行：SELECT id AS deleted
最后一个CTE后面不应该有逗号。请尝试删除该选择之前行末尾的逗号。