使 psql 表成为一对多关系时出现语法错误

Question

我正在尝试为我的后端创建一些基本数据库 API。我想要一个与 order 和 order_products 的一对多关系，所以只能有一个 order(id) 但在“order_products”中可以有更多行与相同的“order_id”但我收到语法错误：

“order”处或附近的语法错误第 2 行：“order_id” int REFERENCES order(id)， ^ 我不知道为什么（这是在 order_products table）。

CREATE TABLE IF NOT EXISTS "customers" (
  "id" SERIAL PRIMARY KEY,
  "first_name" varchar,
  "last_name" varchar,
  "username" varchar,
  "password" varchar,
  "email" varchar UNIQUE,
  "is_admin" boolean 
);

CREATE TABLE IF NOT EXISTS "address" (
  "customer_id" int REFERENCES customers(id),
  "zipcode" int,
  "country" varchar,
  "city" varchar,
  "street_name" varchar,
  "stree_number" varchar,
  "mobile_number" int
);

CREATE TABLE IF NOT EXISTS "products" (
  "id" SERIAL PRIMARY KEY,
  "item_name" varchar UNIQUE,
  "description" text,
  "image_url" varchar,
  "price" float
);

CREATE TABLE IF NOT EXISTS "order" (
  "customer_id" int REFERENCES customers(id),
  "id" SERIAL PRIMARY KEY,
  "date_of_purchase" date,
  "total_price" int
);

CREATE TABLE IF NOT EXISTS "order_products" (
  "order_id" int REFERENCES order(id),
  "product_id" int REFERENCES products(id),
  "quantity" int,
  "total_price" int,
  UNIQUE(order_id, product_id)
);

CREATE TABLE IF NOT EXISTS "cart" (
  "customer_id" int REFERENCES customers(id),
  "id" SERIAL PRIMARY KEY,
  "date_of_purchase" date,
  "total_price" int
);

CREATE TABLE IF NOT EXISTS "cart_products" (
  "cart_id" int REFERENCES cart(id),
  "product_id" int REFERENCES products(id),
  "quantity" int,
  "total_price" int,
  UNIQUE(cart_id, product_id)
);

Answer 1

order是保留关键字，所以需要用双引号总是括起来：

"order_id" int REFERENCES "order"(id),

一般来说，我建议永远不要使用双引号。为此，您需要为 order table 找到一个不需要引用

的不同名称

使 psql 表成为一对多关系时出现语法错误

Syntax error when making psql Tables one-to-many relation

postgresql

foreign-keys

one-to-many

create-table