REFERENCES constraints are not set to the fileds in an intermediate table created by syncdb for SQLite3

[Annadel]

If I have the following class definition:

class Foo(models.Model):

bars = models.ManyToManyField('Bar')
class Meta:

db_table = 'foo'

class Bar(models.Model):

class Meta:

db_table = 'bar'

Then, syncdb will create in SQLite3 the following intermediate table. Note that there is no REFERENCES constrains defined.

CREATE TABLE "foo_bars" (

"id" integer NOT NULL PRIMARY KEY,
"foo_id" integer NOT NULL,
"bar_id" integer NOT NULL,
UNIQUE ("foo_id", "bar_id")

)
CREATE INDEX "foo_bars_e69b476d" ON "foo_bars" ("bar_id");
CREATE INDEX "foo_bars_ef315d12" ON "foo_bars" ("foo_id")

If I define ManyToManyField in Bar class as opposed to Foo class, such as

class Foo(models.Model):

class Meta:

db_table = 'foo'

class Bar(models.Model):

foos = models.ManyToManyField(Foo)
class Meta:

db_table = 'bar'

Then, the intermediate table becomes:

CREATE TABLE "bar_foos" (

"id" integer NOT NULL PRIMARY KEY,
"bar_id" integer NOT NULL,
"foo_id" integer NOT NULL REFERENCES "foo" ("id"),
UNIQUE ("bar_id", "foo_id")

)
CREATE INDEX "bar_foos_e69b476d" ON "foo_bars" ("bar_id");
CREATE INDEX "bar_foos_ef315d12" ON "foo_bars" ("foo_id")

Now only foo_id has REFERENCES constraint.

If I choose MySQL instead of SQLite3, syncdb creates REFERENCE constrains for both foo_id and bar_id, as follows:

CREATE TABLE bar_foos (

id int(11) NOT NULL AUTO_INCREMENT,
bar_id int(11) NOT NULL,
foo_id int(11) NOT NULL,
PRIMARY KEY (id),
UNIQUE KEY bar_id (bar_id,foo_id),
KEY bar_foos_e69b476d (bar_id),
KEY bar_foos_ef315d12 (foo_id),
CONSTRAINT bar_id_refs_id_9d8d0296 FOREIGN KEY (bar_id) REFERENCES bar (id),
CONSTRAINT foo_id_refs_id_27f38014 FOREIGN KEY (foo_id) REFERENCES foo (id)

) ENGINE=InnoDB

So, there seems an issue when syncdb creates an intermediate table derived from ManyToManyField for SQLite3.