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authorMike Bayer <mike_mp@zzzcomputing.com>2010-09-14 17:37:27 -0400
committerMike Bayer <mike_mp@zzzcomputing.com>2010-09-14 17:37:27 -0400
commit60b82d6e13246a3d88e7288e863a5231b7572c6a (patch)
tree30fb5710dd763fd4fbfa9966efe47a4c9e7eace9 /lib/sqlalchemy/schema.py
parentb6fe3a83e9127996cb903ae176701ddfbcca5b12 (diff)
parent46196ea723484f354ac17204ccd489004baaac95 (diff)
downloadsqlalchemy-60b82d6e13246a3d88e7288e863a5231b7572c6a.tar.gz
- merge tip, 0.6.4 + 0.6.5
Diffstat (limited to 'lib/sqlalchemy/schema.py')
-rw-r--r--lib/sqlalchemy/schema.py76
1 files changed, 69 insertions, 7 deletions
diff --git a/lib/sqlalchemy/schema.py b/lib/sqlalchemy/schema.py
index 3e7cad70e..cf00f2b96 100644
--- a/lib/sqlalchemy/schema.py
+++ b/lib/sqlalchemy/schema.py
@@ -142,7 +142,7 @@ class Table(SchemaItem, expression.TableClause):
:param \*args: Additional positional arguments are used primarily
to add the list of :class:`Column` objects contained within this
table. Similar to the style of a CREATE TABLE statement, other
- :class:`SchemaItem` constructs may be added here, including
+ :class:`.SchemaItem` constructs may be added here, including
:class:`PrimaryKeyConstraint`, and :class:`ForeignKeyConstraint`.
:param autoload: Defaults to False: the Columns for this table should
@@ -453,8 +453,22 @@ class Table(SchemaItem, expression.TableClause):
def tometadata(self, metadata, schema=RETAIN_SCHEMA):
- """Return a copy of this ``Table`` associated with a different
- ``MetaData``."""
+ """Return a copy of this :class:`Table` associated with a different
+ :class:`MetaData`.
+
+ E.g.::
+
+ # create two metadata
+ meta1 = MetaData('sqlite:///querytest.db')
+ meta2 = MetaData()
+
+ # load 'users' from the sqlite engine
+ users_table = Table('users', meta1, autoload=True)
+
+ # create the same Table object for the plain metadata
+ users_table_2 = users_table.tometadata(meta2)
+
+ """
try:
if schema is RETAIN_SCHEMA:
@@ -515,7 +529,7 @@ class Column(SchemaItem, expression.ColumnClause):
may not function in all cases.
:param \*args: Additional positional arguments include various
- :class:`SchemaItem` derived constructs which will be applied
+ :class:`.SchemaItem` derived constructs which will be applied
as options to the column. These include instances of
:class:`Constraint`, :class:`ForeignKey`, :class:`ColumnDefault`,
and :class:`Sequence`. In some cases an equivalent keyword
@@ -1246,7 +1260,23 @@ class DefaultGenerator(SchemaItem):
class ColumnDefault(DefaultGenerator):
"""A plain default value on a column.
- This could correspond to a constant, a callable function, or a SQL clause.
+ This could correspond to a constant, a callable function,
+ or a SQL clause.
+
+ :class:`.ColumnDefault` is generated automatically
+ whenever the ``default``, ``onupdate`` arguments of
+ :class:`.Column` are used. A :class:`.ColumnDefault`
+ can be passed positionally as well.
+
+ For example, the following::
+
+ Column('foo', Integer, default=50)
+
+ Is equivalent to::
+
+ Column('foo', Integer, ColumnDefault(50))
+
+
"""
def __init__(self, arg, **kwargs):
@@ -1377,7 +1407,20 @@ class Sequence(DefaultGenerator):
class FetchedValue(object):
- """A default that takes effect on the database side."""
+ """A marker for a transparent database-side default.
+
+ Use :class:`.FetchedValue` when the database is configured
+ to provide some automatic default for a column.
+
+ E.g.::
+
+ Column('foo', Integer, FetchedValue())
+
+ Would indicate that some trigger or default generator
+ will create a new value for the ``foo`` column during an
+ INSERT.
+
+ """
def __init__(self, for_update=False):
self.for_update = for_update
@@ -1394,7 +1437,26 @@ class FetchedValue(object):
class DefaultClause(FetchedValue):
- """A DDL-specified DEFAULT column value."""
+ """A DDL-specified DEFAULT column value.
+
+ :class:`.DefaultClause` is a :class:`.FetchedValue`
+ that also generates a "DEFAULT" clause when
+ "CREATE TABLE" is emitted.
+
+ :class:`.DefaultClause` is generated automatically
+ whenever the ``server_default``, ``server_onupdate`` arguments of
+ :class:`.Column` are used. A :class:`.DefaultClause`
+ can be passed positionally as well.
+
+ For example, the following::
+
+ Column('foo', Integer, server_default="50")
+
+ Is equivalent to::
+
+ Column('foo', Integer, DefaultClause("50"))
+
+ """
def __init__(self, arg, for_update=False):
util.assert_arg_type(arg, (basestring,