Question

我想在sqlite上的一个表中使用许多外键。但它只有一个。我怎么能这样做？

CREATE TABLE STORES(
  SId INTEGER PRIMARY KEY AUTOINCREMENT NOT NULL, 
  SName TEXT NOT NULL
)

CREATE TABLE CITY(
  CId INTEGER PRIMARY KEY AUTOINCREMENT NOT NULL, 
  CName TEXT NOT NULL
)

CREATE TABLE PRODUCTS(
  PId INTEGER PRIMARY KEY AUTOINCREMENT NOT NULL, 
  PName TEXT NOT NULL, 
  Price REAL NOT NULL
)

CREATE TABLE STORE_CITY(
  CId INTEGER REFERENCES CITY(CId) NOT NULL, 
  SId INTEGER REFERENCES STORES(SId) NOT NULL, 
  PId INTEGER REFERENCES PRODUCTS(PId)
)

Answer 1

首先定义列，然后将它们设为外键。

CREATE TABLE STORE_CITY(
  CId INTEGER,
  SId INTEGER,
  PId INTEGER,
  FOREIGN KEY (CId) REFERENCES CITY(CId) NOT NULL, 
  FOREIGN KEY (SId) REFERENCES STORES(SId) NOT NULL, 
  FOREIGN KEY (PId) REFERENCES PRODUCTS(PId)
)

一个表sqlite中的许多外键

1 个答案: