BEGIN (implicit)
INSERT INTO users (name, fullname, password) VALUES (?, ?, ?)
('ed', 'Ed Jones', 'edspassword')
- SELECT users.id AS users_id, users.name AS users_name, users.fullname AS users_fullname, users.password AS users_password
+ SELECT users.id AS users_id,
+ users.name AS users_name,
+ users.fullname AS users_fullname,
+ users.password AS users_password
FROM users
WHERE users.name = ?
LIMIT ? OFFSET ?
>>> ed_user.password = 'f8s7ccs'
-The :class:`~sqlalchemy.orm.session.Session` is paying attention. It knows, for example, that ``Ed Jones`` has been modified:
+The :class:`~sqlalchemy.orm.session.Session` is paying attention. It knows,
+for example, that ``Ed Jones`` has been modified:
.. sourcecode:: python+sql
{sql}>>> ed_user.id # doctest: +NORMALIZE_WHITESPACE
BEGIN (implicit)
- SELECT users.id AS users_id, users.name AS users_name, users.fullname AS users_fullname, users.password AS users_password
+ SELECT users.id AS users_id,
+ users.name AS users_name,
+ users.fullname AS users_fullname,
+ users.password AS users_password
FROM users
WHERE users.id = ?
(1,)
('Edwardo', 1)
INSERT INTO users (name, fullname, password) VALUES (?, ?, ?)
('fakeuser', 'Invalid', '12345')
- SELECT users.id AS users_id, users.name AS users_name, users.fullname AS users_fullname, users.password AS users_password
+ SELECT users.id AS users_id,
+ users.name AS users_name,
+ users.fullname AS users_fullname,
+ users.password AS users_password
FROM users
WHERE users.name IN (?, ?)
('Edwardo', 'fakeuser')
{stop}[<User('Edwardo','Ed Jones', 'f8s7ccs')>, <User('fakeuser','Invalid', '12345')>]
-Rolling back, we can see that ``ed_user``'s name is back to ``ed``, and ``fake_user`` has been kicked out of the session:
+Rolling back, we can see that ``ed_user``'s name is back to ``ed``, and
+``fake_user`` has been kicked out of the session:
.. sourcecode:: python+sql
{sql}>>> ed_user.name #doctest: +NORMALIZE_WHITESPACE
BEGIN (implicit)
- SELECT users.id AS users_id, users.name AS users_name, users.fullname AS users_fullname, users.password AS users_password
+ SELECT users.id AS users_id,
+ users.name AS users_name,
+ users.fullname AS users_fullname,
+ users.password AS users_password
FROM users
WHERE users.id = ?
(1,)
.. sourcecode:: python+sql
{sql}>>> session.query(User).filter(User.name.in_(['ed', 'fakeuser'])).all() #doctest: +NORMALIZE_WHITESPACE
- SELECT users.id AS users_id, users.name AS users_name, users.fullname AS users_fullname, users.password AS users_password
+ SELECT users.id AS users_id,
+ users.name AS users_name,
+ users.fullname AS users_fullname,
+ users.password AS users_password
FROM users
WHERE users.name IN (?, ?)
('ed', 'fakeuser')
{sql}>>> for instance in session.query(User).order_by(User.id): # doctest: +NORMALIZE_WHITESPACE
... print instance.name, instance.fullname
- SELECT users.id AS users_id, users.name AS users_name,
- users.fullname AS users_fullname, users.password AS users_password
+ SELECT users.id AS users_id,
+ users.name AS users_name,
+ users.fullname AS users_fullname,
+ users.password AS users_password
FROM users ORDER BY users.id
()
{stop}ed Ed Jones
{sql}>>> for name, fullname in session.query(User.name, User.fullname): # doctest: +NORMALIZE_WHITESPACE
... print name, fullname
- SELECT users.name AS users_name, users.fullname AS users_fullname
+ SELECT users.name AS users_name,
+ users.fullname AS users_fullname
FROM users
()
{stop}ed Ed Jones
{sql}>>> for row in session.query(User, User.name).all(): #doctest: +NORMALIZE_WHITESPACE
... print row.User, row.name
- SELECT users.id AS users_id, users.name AS users_name, users.fullname AS users_fullname, users.password AS users_password
+ SELECT users.id AS users_id,
+ users.name AS users_name,
+ users.fullname AS users_fullname,
+ users.password AS users_password
FROM users
()
{stop}<User('ed','Ed Jones', 'f8s7ccs')> ed
{sql}>>> for u in session.query(User).order_by(User.id)[1:3]: #doctest: +NORMALIZE_WHITESPACE
... print u
- SELECT users.id AS users_id, users.name AS users_name, users.fullname AS users_fullname, users.password AS users_password
+ SELECT users.id AS users_id,
+ users.name AS users_name,
+ users.fullname AS users_fullname,
+ users.password AS users_password
FROM users ORDER BY users.id
LIMIT ? OFFSET ?
(2, 1){stop}
.. sourcecode:: python+sql
- {sql}>>> for name, in session.query(User.name).filter_by(fullname='Ed Jones'): # doctest: +NORMALIZE_WHITESPACE
+ {sql}>>> for name, in session.query(User.name).\
+ ... filter_by(fullname='Ed Jones'): # doctest: +NORMALIZE_WHITESPACE
... print name
SELECT users.name AS users_name FROM users
WHERE users.fullname = ?
.. sourcecode:: python+sql
- {sql}>>> for name, in session.query(User.name).filter(User.fullname=='Ed Jones'): # doctest: +NORMALIZE_WHITESPACE
+ {sql}>>> for name, in session.query(User.name).\
+ ... filter(User.fullname=='Ed Jones'): # doctest: +NORMALIZE_WHITESPACE
... print name
SELECT users.name AS users_name FROM users
WHERE users.fullname = ?
.. sourcecode:: python+sql
- {sql}>>> for user in session.query(User).filter(User.name=='ed').filter(User.fullname=='Ed Jones'): # doctest: +NORMALIZE_WHITESPACE
+ {sql}>>> for user in session.query(User).\
+ ... filter(User.name=='ed').\
+ ... filter(User.fullname=='Ed Jones'): # doctest: +NORMALIZE_WHITESPACE
... print user
- SELECT users.id AS users_id, users.name AS users_name, users.fullname AS users_fullname, users.password AS users_password
+ SELECT users.id AS users_id,
+ users.name AS users_name,
+ users.fullname AS users_fullname,
+ users.password AS users_password
FROM users
WHERE users.name = ? AND users.fullname = ?
('ed', 'Ed Jones')
>>> query = session.query(User).filter(User.name.like('%ed')).order_by(User.id)
{sql}>>> query.all() #doctest: +NORMALIZE_WHITESPACE
- SELECT users.id AS users_id, users.name AS users_name, users.fullname AS users_fullname, users.password AS users_password
+ SELECT users.id AS users_id,
+ users.name AS users_name,
+ users.fullname AS users_fullname,
+ users.password AS users_password
FROM users
WHERE users.name LIKE ? ORDER BY users.id
('%ed',)
.. sourcecode:: python+sql
{sql}>>> query.first() #doctest: +NORMALIZE_WHITESPACE
- SELECT users.id AS users_id, users.name AS users_name, users.fullname AS users_fullname, users.password AS users_password
+ SELECT users.id AS users_id,
+ users.name AS users_name,
+ users.fullname AS users_fullname,
+ users.password AS users_password
FROM users
WHERE users.name LIKE ? ORDER BY users.id
LIMIT ? OFFSET ?
... user = query.one()
... except MultipleResultsFound, e:
... print e
- SELECT users.id AS users_id, users.name AS users_name, users.fullname AS users_fullname, users.password AS users_password
+ SELECT users.id AS users_id,
+ users.name AS users_name,
+ users.fullname AS users_fullname,
+ users.password AS users_password
FROM users
WHERE users.name LIKE ? ORDER BY users.id
('%ed',)
... user = query.filter(User.id == 99).one()
... except NoResultFound, e:
... print e
- SELECT users.id AS users_id, users.name AS users_name, users.fullname AS users_fullname, users.password AS users_password
+ SELECT users.id AS users_id,
+ users.name AS users_name,
+ users.fullname AS users_fullname,
+ users.password AS users_password
FROM users
WHERE users.name LIKE ? AND users.id = ? ORDER BY users.id
('%ed', 99)
.. sourcecode:: python+sql
- {sql}>>> for user in session.query(User).filter("id<224").order_by("id").all(): #doctest: +NORMALIZE_WHITESPACE
+ {sql}>>> for user in session.query(User).\
+ ... filter("id<224").\
+ ... order_by("id").all(): #doctest: +NORMALIZE_WHITESPACE
... print user.name
- SELECT users.id AS users_id, users.name AS users_name, users.fullname AS users_fullname, users.password AS users_password
+ SELECT users.id AS users_id,
+ users.name AS users_name,
+ users.fullname AS users_fullname,
+ users.password AS users_password
FROM users
WHERE id<224 ORDER BY id
()
{sql}>>> session.query(User).filter("id<:value and name=:name").\
... params(value=224, name='fred').order_by(User.id).one() # doctest: +NORMALIZE_WHITESPACE
- SELECT users.id AS users_id, users.name AS users_name, users.fullname AS users_fullname, users.password AS users_password
+ SELECT users.id AS users_id,
+ users.name AS users_name,
+ users.fullname AS users_fullname,
+ users.password AS users_password
FROM users
WHERE id<? and name=? ORDER BY users.id
(224, 'fred')
.. sourcecode:: python+sql
- >>> jack.addresses = [Address(email_address='jack@google.com'), Address(email_address='j25@yahoo.com')]
+ >>> jack.addresses = [
+ ... Address(email_address='jack@google.com'),
+ ... Address(email_address='j25@yahoo.com')]
When using a bidirectional relationship, elements added in one direction
automatically become visible in the other direction. This behavior occurs
{sql}>>> jack = session.query(User).\
... filter_by(name='jack').one() #doctest: +NORMALIZE_WHITESPACE
BEGIN (implicit)
- SELECT users.id AS users_id, users.name AS users_name,
- users.fullname AS users_fullname, users.password AS users_password
+ SELECT users.id AS users_id,
+ users.name AS users_name,
+ users.fullname AS users_fullname,
+ users.password AS users_password
FROM users
WHERE users.name = ?
('jack',)
.. sourcecode:: python+sql
{sql}>>> jack.addresses #doctest: +NORMALIZE_WHITESPACE
- SELECT addresses.id AS addresses_id, addresses.email_address AS
- addresses_email_address, addresses.user_id AS addresses_user_id
+ SELECT addresses.id AS addresses_id,
+ addresses.email_address AS
+ addresses_email_address,
+ addresses.user_id AS addresses_user_id
FROM addresses
WHERE ? = addresses.user_id ORDER BY addresses.id
(5,)
.. sourcecode:: python+sql
- {sql}>>> for u, a in session.query(User, Address).filter(User.id==Address.user_id).\
- ... filter(Address.email_address=='jack@google.com').all(): # doctest: +NORMALIZE_WHITESPACE
+ {sql}>>> for u, a in session.query(User, Address).\
+ ... filter(User.id==Address.user_id).\
+ ... filter(Address.email_address=='jack@google.com').\
+ ... all(): # doctest: +NORMALIZE_WHITESPACE
... print u, a
SELECT users.id AS users_id,
users.name AS users_name,
addresses.email_address AS addresses_email_address,
addresses.user_id AS addresses_user_id
FROM users, addresses
- WHERE users.id = addresses.user_id AND addresses.email_address = ?
+ WHERE users.id = addresses.user_id
+ AND addresses.email_address = ?
('jack@google.com',)
{stop}<User('jack','Jack Bean', 'gjffdd')> <Address('jack@google.com')>
.. sourcecode:: python+sql
{sql}>>> session.query(User).join(Address).\
- ... filter(Address.email_address=='jack@google.com').all() #doctest: +NORMALIZE_WHITESPACE
+ ... filter(Address.email_address=='jack@google.com').\
+ ... all() #doctest: +NORMALIZE_WHITESPACE
SELECT users.id AS users_id,
users.name AS users_name,
users.fullname AS users_fullname,
... filter(adalias1.email_address=='jack@google.com').\
... filter(adalias2.email_address=='j25@yahoo.com'):
... print username, email1, email2 # doctest: +NORMALIZE_WHITESPACE
- SELECT users.name AS users_name, addresses_1.email_address AS addresses_1_email_address,
- addresses_2.email_address AS addresses_2_email_address
- FROM users JOIN addresses AS addresses_1 ON users.id = addresses_1.user_id
- JOIN addresses AS addresses_2 ON users.id = addresses_2.user_id
- WHERE addresses_1.email_address = ? AND addresses_2.email_address = ?
+ SELECT users.name AS users_name,
+ addresses_1.email_address AS addresses_1_email_address,
+ addresses_2.email_address AS addresses_2_email_address
+ FROM users JOIN addresses AS addresses_1
+ ON users.id = addresses_1.user_id
+ JOIN addresses AS addresses_2
+ ON users.id = addresses_2.user_id
+ WHERE addresses_1.email_address = ?
+ AND addresses_2.email_address = ?
('jack@google.com', 'j25@yahoo.com')
{stop}jack jack@google.com j25@yahoo.com
get rows back for those users who don't have any addresses, e.g.::
SELECT users.*, adr_count.address_count FROM users LEFT OUTER JOIN
- (SELECT user_id, count(*) AS address_count FROM addresses GROUP BY user_id) AS adr_count
+ (SELECT user_id, count(*) AS address_count
+ FROM addresses GROUP BY user_id) AS adr_count
ON users.id=adr_count.user_id
Using the :class:`~sqlalchemy.orm.query.Query`, we build a statement like this
construct, which are described in :ref:`sqlexpression_toplevel`::
>>> from sqlalchemy.sql import func
- >>> stmt = session.query(Address.user_id, func.count('*').label('address_count')).group_by(Address.user_id).subquery()
+ >>> stmt = session.query(Address.user_id, func.count('*').\
+ ... label('address_count')).\
+ ... group_by(Address.user_id).subquery()
The ``func`` keyword generates SQL functions, and the ``subquery()`` method on
:class:`~sqlalchemy.orm.query.Query` produces a SQL expression construct
{sql}>>> for u, count in session.query(User, stmt.c.address_count).\
... outerjoin(stmt, User.id==stmt.c.user_id).order_by(User.id): # doctest: +NORMALIZE_WHITESPACE
... print u, count
- SELECT users.id AS users_id, users.name AS users_name,
- users.fullname AS users_fullname, users.password AS users_password,
- anon_1.address_count AS anon_1_address_count
- FROM users LEFT OUTER JOIN (SELECT addresses.user_id AS user_id, count(?) AS address_count
- FROM addresses GROUP BY addresses.user_id) AS anon_1 ON users.id = anon_1.user_id
+ SELECT users.id AS users_id,
+ users.name AS users_name,
+ users.fullname AS users_fullname,
+ users.password AS users_password,
+ anon_1.address_count AS anon_1_address_count
+ FROM users LEFT OUTER JOIN
+ (SELECT addresses.user_id AS user_id, count(?) AS address_count
+ FROM addresses GROUP BY addresses.user_id) AS anon_1
+ ON users.id = anon_1.user_id
ORDER BY users.id
('*',)
{stop}<User('ed','Ed Jones', 'f8s7ccs')> None
.. sourcecode:: python+sql
- {sql}>>> stmt = session.query(Address).filter(Address.email_address != 'j25@yahoo.com').subquery()
+ {sql}>>> stmt = session.query(Address).\
+ ... filter(Address.email_address != 'j25@yahoo.com').\
+ ... subquery()
>>> adalias = aliased(Address, stmt)
- >>> for user, address in session.query(User, adalias).join(adalias, User.addresses): # doctest: +NORMALIZE_WHITESPACE
+ >>> for user, address in session.query(User, adalias).\
+ ... join(adalias, User.addresses): # doctest: +NORMALIZE_WHITESPACE
... print user, address
- SELECT users.id AS users_id, users.name AS users_name, users.fullname AS users_fullname,
- users.password AS users_password, anon_1.id AS anon_1_id,
- anon_1.email_address AS anon_1_email_address, anon_1.user_id AS anon_1_user_id
- FROM users JOIN (SELECT addresses.id AS id, addresses.email_address AS email_address, addresses.user_id AS user_id
- FROM addresses
- WHERE addresses.email_address != ?) AS anon_1 ON users.id = anon_1.user_id
+ SELECT users.id AS users_id,
+ users.name AS users_name,
+ users.fullname AS users_fullname,
+ users.password AS users_password,
+ anon_1.id AS anon_1_id,
+ anon_1.email_address AS anon_1_email_address,
+ anon_1.user_id AS anon_1_user_id
+ FROM users JOIN
+ (SELECT addresses.id AS id,
+ addresses.email_address AS email_address,
+ addresses.user_id AS user_id
+ FROM addresses
+ WHERE addresses.email_address != ?) AS anon_1
+ ON users.id = anon_1.user_id
('j25@yahoo.com',)
{stop}<User('jack','Jack Bean', 'gjffdd')> <Address('jack@google.com')>
.. sourcecode:: python+sql
- {sql}>>> for name, in session.query(User.name).filter(User.addresses.any()): # doctest: +NORMALIZE_WHITESPACE
+ {sql}>>> for name, in session.query(User.name).\
+ ... filter(User.addresses.any()): # doctest: +NORMALIZE_WHITESPACE
... print name
SELECT users.name AS users_name
FROM users
.. sourcecode:: python+sql
- {sql}>>> session.query(Address).filter(~Address.user.has(User.name=='jack')).all() # doctest: +NORMALIZE_WHITESPACE
- SELECT addresses.id AS addresses_id, addresses.email_address AS addresses_email_address,
- addresses.user_id AS addresses_user_id
+ {sql}>>> session.query(Address).\
+ ... filter(~Address.user.has(User.name=='jack')).all() # doctest: +NORMALIZE_WHITESPACE
+ SELECT addresses.id AS addresses_id,
+ addresses.email_address AS addresses_email_address,
+ addresses.user_id AS addresses_user_id
FROM addresses
WHERE NOT (EXISTS (SELECT 1
FROM users
# load Jack by primary key
{sql}>>> jack = session.query(User).get(5) #doctest: +NORMALIZE_WHITESPACE
BEGIN (implicit)
- SELECT users.id AS users_id, users.name AS users_name, users.fullname AS users_fullname, users.password AS users_password
+ SELECT users.id AS users_id,
+ users.name AS users_name,
+ users.fullname AS users_fullname,
+ users.password AS users_password
FROM users
WHERE users.id = ?
(5,)
# remove one Address (lazy load fires off)
{sql}>>> del jack.addresses[1] #doctest: +NORMALIZE_WHITESPACE
- SELECT addresses.id AS addresses_id, addresses.email_address AS addresses_email_address, addresses.user_id AS addresses_user_id
+ SELECT addresses.id AS addresses_id,
+ addresses.email_address AS addresses_email_address,
+ addresses.user_id AS addresses_user_id
FROM addresses
WHERE ? = addresses.user_id
(5,)
('jack@google.com', 'j25@yahoo.com')
{stop}0
+.. topic:: More on Cascades
+
+ Further detail on configuration of cascades is at :ref:`unitofwork_cascades`.
+ The cascade functionality can also integrate smoothly with
+ the ``ON DELETE CASCADE`` functionality of the relational database.
+ See :ref:`passive_deletes` for details.
+
Building a Many To Many Relationship
====================================
.. sourcecode:: python+sql
- {sql}>>> wendy = session.query(User).filter_by(name='wendy').one() #doctest: +NORMALIZE_WHITESPACE
- SELECT users.id AS users_id, users.name AS users_name, users.fullname AS users_fullname, users.password AS users_password
+ {sql}>>> wendy = session.query(User).\
+ ... filter_by(name='wendy').\
+ ... one() #doctest: +NORMALIZE_WHITESPACE
+ SELECT users.id AS users_id,
+ users.name AS users_name,
+ users.fullname AS users_fullname,
+ users.password AS users_password
FROM users
WHERE users.name = ?
('wendy',)
.. sourcecode:: python+sql
- {sql}>>> session.query(BlogPost).filter(BlogPost.keywords.any(keyword='firstpost')).all() #doctest: +NORMALIZE_WHITESPACE
+ {sql}>>> session.query(BlogPost).\
+ ... filter(BlogPost.keywords.any(keyword='firstpost')).\
+ ... all() #doctest: +NORMALIZE_WHITESPACE
INSERT INTO keywords (keyword) VALUES (?)
('wendy',)
INSERT INTO keywords (keyword) VALUES (?)
(2, "Wendy's Blog Post", 'This is a test')
INSERT INTO post_keywords (post_id, keyword_id) VALUES (?, ?)
((1, 1), (1, 2))
- SELECT posts.id AS posts_id, posts.user_id AS posts_user_id, posts.headline AS posts_headline, posts.body AS posts_body
+ SELECT posts.id AS posts_id,
+ posts.user_id AS posts_user_id,
+ posts.headline AS posts_headline,
+ posts.body AS posts_body
FROM posts
WHERE EXISTS (SELECT 1
- FROM post_keywords, keywords
- WHERE posts.id = post_keywords.post_id AND keywords.id = post_keywords.keyword_id AND keywords.keyword = ?)
+ FROM post_keywords, keywords
+ WHERE posts.id = post_keywords.post_id
+ AND keywords.id = post_keywords.keyword_id
+ AND keywords.keyword = ?)
('firstpost',)
{stop}[BlogPost("Wendy's Blog Post", 'This is a test', <User('wendy','Wendy Williams', 'foobar')>)]
.. sourcecode:: python+sql
- {sql}>>> session.query(BlogPost).filter(BlogPost.author==wendy).\
- ... filter(BlogPost.keywords.any(keyword='firstpost')).all() #doctest: +NORMALIZE_WHITESPACE
- SELECT posts.id AS posts_id, posts.user_id AS posts_user_id, posts.headline AS posts_headline, posts.body AS posts_body
+ {sql}>>> session.query(BlogPost).\
+ ... filter(BlogPost.author==wendy).\
+ ... filter(BlogPost.keywords.any(keyword='firstpost')).\
+ ... all() #doctest: +NORMALIZE_WHITESPACE
+ SELECT posts.id AS posts_id,
+ posts.user_id AS posts_user_id,
+ posts.headline AS posts_headline,
+ posts.body AS posts_body
FROM posts
WHERE ? = posts.user_id AND (EXISTS (SELECT 1
- FROM post_keywords, keywords
- WHERE posts.id = post_keywords.post_id AND keywords.id = post_keywords.keyword_id AND keywords.keyword = ?))
+ FROM post_keywords, keywords
+ WHERE posts.id = post_keywords.post_id
+ AND keywords.id = post_keywords.keyword_id
+ AND keywords.keyword = ?))
(2, 'firstpost')
{stop}[BlogPost("Wendy's Blog Post", 'This is a test', <User('wendy','Wendy Williams', 'foobar')>)]
.. sourcecode:: python+sql
- {sql}>>> wendy.posts.filter(BlogPost.keywords.any(keyword='firstpost')).all() #doctest: +NORMALIZE_WHITESPACE
- SELECT posts.id AS posts_id, posts.user_id AS posts_user_id, posts.headline AS posts_headline, posts.body AS posts_body
+ {sql}>>> wendy.posts.\
+ ... filter(BlogPost.keywords.any(keyword='firstpost')).\
+ ... all() #doctest: +NORMALIZE_WHITESPACE
+ SELECT posts.id AS posts_id,
+ posts.user_id AS posts_user_id,
+ posts.headline AS posts_headline,
+ posts.body AS posts_body
FROM posts
WHERE ? = posts.user_id AND (EXISTS (SELECT 1
- FROM post_keywords, keywords
- WHERE posts.id = post_keywords.post_id AND keywords.id = post_keywords.keyword_id AND keywords.keyword = ?))
+ FROM post_keywords, keywords
+ WHERE posts.id = post_keywords.post_id
+ AND keywords.id = post_keywords.keyword_id
+ AND keywords.keyword = ?))
(2, 'firstpost')
{stop}[BlogPost("Wendy's Blog Post", 'This is a test', <User('wendy','Wendy Williams', 'foobar')>)]
projects / thirdparty / sqlalchemy / sqlalchemy.git / commitdiff
