#!/usr/bin/env python3
import sqlite3

print(sqlite3.sqlite_version)

con = sqlite3.connect(':memory:')

a = "create table a (id integer primary key,name text)"
con.execute(a)

b = "create table b (id integer primary key,r integer,foreign key(r) references a(id) on delete cascade)"
con.execute(b)
con.commit()

a = "insert into a (name) values (\"abc\")"
con.execute(a)
con.commit()

print(con.execute("select * from a").fetchall())

a = "insert into b (r) values (1)"
con.execute(a)
con.commit()

print(con.execute("select * from b").fetchall())

a = "delete from a where id=1"
con.execute(a)
con.commit()

print(con.execute("select * from b").fetchall())
print(con.execute("select * from a").fetchall())

我得到这些结果：

3.7.4
[(1,'abc')]
[(1,1)]
[(1,1)]
[]

这证明级联没有发生.我做错了什么或者获得与级联相同结果的解决方案是什么？