[Sqlalchemy-commits] [1102] sqlalchemy/trunk/lib/sqlalchemy: a mapper with inheritance will place it
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[Sqlalchemy-commits] [1102] sqlalchemy/trunk/lib/sqlalchemy: a mapper with inheritance will place itself as "dependent" on the inherited mapper; even though this is not usually needed, it allows certain exotic combinations of mapper setups to work (i.e.
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.1//EN" "http://www.w3.org/TR/xhtml11/DTD/xhtml11.dtd"> <html xmlns="http://www.w3.org/1999/xhtml"> <head><style type="text/css"><!-- #msg dl { border: 1px #006 solid; background: #369; padding: 6px; color: #fff; } #msg dt { float: left; width: 6em; font-weight: bold; } #msg dt:after { content:':';} #msg dl, #msg dt, #msg ul, #msg li { font-family: verdana,arial,helvetica,sans-serif; font-size: 10pt; } #msg dl a { font-weight: bold} #msg dl a:link { color:#fc3; } #msg dl a:active { color:#ff0; } #msg dl a:visited { color:#cc6; } h3 { font-family: verdana,arial,helvetica,sans-serif; font-size: 10pt; font-weight: bold; } #msg pre { overflow: auto; background: #ffc; border: 1px #fc0 solid; padding: 6px; } #msg ul, pre { overflow: auto; } #patch { width: 100%; } #patch h4 {font-family: verdana,arial,helvetica,sans-serif;font-size:10pt;padding:8px;background:#369;color:#fff;margin:0;} #patch .propset h4, #patch .binary h4 {margin:0;} #patch pre {padding:0;line-height:1.2em;margin:0;} #patch .diff {width:100%;background:#eee;padding: 0 0 10px 0;overflow:auto;} #patch .propset .diff, #patch .binary .diff {padding:10px 0;} #patch span {display:block;padding:0 10px;} #patch .modfile, #patch .addfile, #patch .delfile, #patch .propset, #patch .binary, #patch .copfile {border:1px solid #ccc;margin:10px 0;} #patch ins {background:#dfd;text-decoration:none;display:block;padding:0 10px;} #patch del {background:#fdd;text-decoration:none;display:block;padding:0 10px;} #patch .lines, .info {color:#888;background:#fff;} --></style> <title>[1102] sqlalchemy/trunk/lib/sqlalchemy: a mapper with inheritance will place itself as "dependent" on the inherited mapper; even though this is not usually needed, it allows certain exotic combinations of mapper setups to work (i.e.</title> </head> <body> <div id="msg"> <dl> <dt>Revision</dt> <dd>1102</dd> <dt>Author</dt> <dd>zzzeek</dd> <dt>Date</dt> <dd>2006-03-05 21:10:46 -0600 (Sun, 05 Mar 2006)</dd> </dl> <h3>Log Message</h3> <pre>a mapper with inheritance will place itself as "dependent" on the inherited mapper; even though this is not usually needed, it allows certain exotic combinations of mapper setups to work (i.e. the one in the polymorph example)</pre> <h3>Modified Paths</h3> <ul> <li><a href="#sqlalchemytrunkexamplespolymorphpolymorphpy">sqlalchemy/trunk/examples/polymorph/polymorph.py</a></li> <li><a href="#sqlalchemytrunklibsqlalchemymappingmapperpy">sqlalchemy/trunk/lib/sqlalchemy/mapping/mapper.py</a></li> <li><a href="#sqlalchemytrunklibsqlalchemymappingobjectstorepy">sqlalchemy/trunk/lib/sqlalchemy/mapping/objectstore.py</a></li> <li><a href="#sqlalchemytrunklibsqlalchemysqlpy">sqlalchemy/trunk/lib/sqlalchemy/sql.py</a></li> </ul> </div> <div id="patch"> <h3>Diff</h3> <a id="sqlalchemytrunkexamplespolymorphpolymorphpy"></a> <div class="modfile"><h4>Modified: sqlalchemy/trunk/examples/polymorph/polymorph.py (1101 => 1102)</h4> <pre class="diff"><span> <span class="info">--- sqlalchemy/trunk/examples/polymorph/polymorph.py 2006-03-06 02:27:13 UTC (rev 1101) +++ sqlalchemy/trunk/examples/polymorph/polymorph.py 2006-03-06 03:10:46 UTC (rev 1102) </span><span class="lines">@@ -6,7 +6,8 @@ </span><span class="cx"> # extend from a common base class, although this same approach can be used </span><span class="cx"> # with </span><span class="cx"> </span><del>-db = create_engine('sqlite://', echo=True, echo_uow=False) </del><ins>+#db = create_engine('sqlite://', echo=True, echo_uow=False) +db = create_engine('postgres://user=scott&password=tiger&host=127.0.0.1&database=test', echo=True, echo_uow=False) </ins><span class="cx"> </span><span class="cx"> # a table to store companies </span><span class="cx"> companies = Table('companies', db, </span><span class="lines">@@ -52,9 +53,10 @@ </span><span class="cx"> assign_mapper(Manager, managers, inherits=Person.mapper) </span><span class="cx"> </span><span class="cx"> # next, we define a query that is going to load Managers and Engineers in one shot. </span><del>-# this query is tricky since the managers and engineers tables contain the same "description" column, -# so we set up a full blown select() statement that uses aliases for the description -# column. The select() statement is also given an alias 'pjoin', since the mapper requires </del><ins>+# we will use a UNION ALL with an extra hardcoded column to indicate the type of object. +# this can also be done via several LEFT OUTER JOINS but a UNION is more appropriate +# since they are distinct result sets. +# The select() statement is also given an alias 'pjoin', since the mapper requires </ins><span class="cx"> # that all Selectables have a name. </span><span class="cx"> # </span><span class="cx"> # TECHNIQUE - when you want to load a certain set of objects from a in one query, all the </span><span class="lines">@@ -65,7 +67,7 @@ </span><span class="cx"> # </span><span class="cx"> person_join = select( </span><span class="cx"> [people, managers.c.description,column("'manager'").label('type')], </span><del>- people.c.person_id==managers.c.person_id).union( </del><ins>+ people.c.person_id==managers.c.person_id).union_all( </ins><span class="cx"> select( </span><span class="cx"> [people, engineers.c.description, column("'engineer'").label('type')], </span><span class="cx"> people.c.person_id==engineers.c.person_id)).alias('pjoin') </span><span class="lines">@@ -89,20 +91,24 @@ </span><span class="cx"> ext = PersonLoader() </span><span class="cx"> </span><span class="cx"> # set up the polymorphic mapper, which maps the person_join we set up to </span><del>-# the Person class, using an instance of PersonLoader. Note that even though -# this mapper is against Person, its not going to screw up the normal operation -# of the Person object since its not the "primary" mapper. In reality, we could even -# make this mapper against some other class we dont care about since the creation of -# objects is hardcoded. </del><ins>+# the Person class, using an instance of PersonLoader. </ins><span class="cx"> people_mapper = mapper(Person, person_join, extension=ext) </span><span class="cx"> </span><ins>+# create a mapper for Company. the 'employees' relationship points to +# our new people_mapper. +# +# the dependency relationships which take effect on commit (i.e. the order of +# inserts/deletes) will be established against the Person class's primary +# mapper, and when the Engineer and +# Manager objects are found in the 'employees' list, the primary mappers +# for those subclasses will register +# themselves as dependent on the Person mapper's save operations. +# (translation: it'll work) +# TODO: get the eager loading to work (the compound select alias doesnt like being aliased itself) </ins><span class="cx"> assign_mapper(Company, companies, properties={ </span><del>- 'employees': relation(people_mapper), - 'engineers': relation(Engineer, private=True), - 'managers':relation(Manager, private=True) </del><ins>+ 'employees': relation(people_mapper, private=True) </ins><span class="cx"> }) </span><span class="cx"> </span><del>- </del><span class="cx"> c = Company(name='company1') </span><span class="cx"> c.employees.append(Manager(name='pointy haired boss', description='manager1')) </span><span class="cx"> c.employees.append(Engineer(name='dilbert', description='engineer1')) </span><span class="lines">@@ -128,4 +134,10 @@ </span><span class="cx"> print e, e._instance_key </span><span class="cx"> </span><span class="cx"> objectstore.delete(c) </span><del>-objectstore.commit() </del><span class="cx">\ No newline at end of file </span><ins>+objectstore.commit() + + +managers.drop() +engineers.drop() +people.drop() +companies.drop() </ins></span></pre></div> <a id="sqlalchemytrunklibsqlalchemymappingmapperpy"></a> <div class="modfile"><h4>Modified: sqlalchemy/trunk/lib/sqlalchemy/mapping/mapper.py (1101 => 1102)</h4> <pre class="diff"><span> <span class="info">--- sqlalchemy/trunk/lib/sqlalchemy/mapping/mapper.py 2006-03-06 02:27:13 UTC (rev 1101) +++ sqlalchemy/trunk/lib/sqlalchemy/mapping/mapper.py 2006-03-06 03:10:46 UTC (rev 1102) </span><span class="lines">@@ -67,9 +67,11 @@ </span><span class="cx"> self.table = sql.join(inherits.table, table, inherit_condition) </span><span class="cx"> self._synchronizer = sync.ClauseSynchronizer(self, self, sync.ONETOMANY) </span><span class="cx"> self._synchronizer.compile(self.table.onclause, inherits.tables, TableFinder(table)) </span><ins>+ self.inherits = inherits </ins><span class="cx"> else: </span><span class="cx"> self.primarytable = self.table </span><span class="cx"> self._synchronizer = None </span><ins>+ self.inherits = None </ins><span class="cx"> </span><span class="cx"> # locate all tables contained within the "table" passed in, which </span><span class="cx"> # may be a join or other construct </span><span class="lines">@@ -670,13 +672,15 @@ </span><span class="cx"> except KeyError: </span><span class="cx"> return False </span><span class="cx"> </span><del>- def register_dependencies(self, *args, **kwargs): </del><ins>+ def register_dependencies(self, uowcommit, *args, **kwargs): </ins><span class="cx"> """called by an instance of objectstore.UOWTransaction to register </span><span class="cx"> which mappers are dependent on which, as well as DependencyProcessor </span><span class="cx"> objects which will process lists of objects in between saves and deletes.""" </span><span class="cx"> for prop in self.props.values(): </span><del>- prop.register_dependencies(*args, **kwargs) - </del><ins>+ prop.register_dependencies(uowcommit, *args, **kwargs) + if self.inherits is not None: + uowcommit.register_dependency(self.inherits, self) + </ins><span class="cx"> def register_deleted(self, obj, uow): </span><span class="cx"> for prop in self.props.values(): </span><span class="cx"> prop.register_deleted(obj, uow) </span></span></pre></div> <a id="sqlalchemytrunklibsqlalchemymappingobjectstorepy"></a> <div class="modfile"><h4>Modified: sqlalchemy/trunk/lib/sqlalchemy/mapping/objectstore.py (1101 => 1102)</h4> <pre class="diff"><span> <span class="info">--- sqlalchemy/trunk/lib/sqlalchemy/mapping/objectstore.py 2006-03-06 02:27:13 UTC (rev 1101) +++ sqlalchemy/trunk/lib/sqlalchemy/mapping/objectstore.py 2006-03-06 03:10:46 UTC (rev 1102) </span><span class="lines">@@ -534,7 +534,6 @@ </span><span class="cx"> def register_dependency(self, mapper, dependency): </span><span class="cx"> """called by mapper.PropertyLoader to register the objects handled by </span><span class="cx"> one mapper being dependent on the objects handled by another.""" </span><del>- </del><span class="cx"> # correct for primary mapper (the mapper offcially associated with the class) </span><span class="cx"> self.dependencies[(mapper._primary_mapper(), dependency._primary_mapper())] = True </span><span class="cx"> self.__modified = True </span></span></pre></div> <a id="sqlalchemytrunklibsqlalchemysqlpy"></a> <div class="modfile"><h4>Modified: sqlalchemy/trunk/lib/sqlalchemy/sql.py (1101 => 1102)</h4> <pre class="diff"><span> <span class="info">--- sqlalchemy/trunk/lib/sqlalchemy/sql.py 2006-03-06 02:27:13 UTC (rev 1101) +++ sqlalchemy/trunk/lib/sqlalchemy/sql.py 2006-03-06 03:10:46 UTC (rev 1102) </span><span class="lines">@@ -1211,7 +1211,6 @@ </span><span class="cx"> self.visit_select(cs) </span><span class="cx"> for s in cs.selects: </span><span class="cx"> s.parens = False </span><del>- print "BUT", id(cs), cs.parens </del><span class="cx"> def visit_column(self, c):pass </span><span class="cx"> def visit_table(self, c):pass </span><span class="cx"> def visit_select(self, select): </span></span></pre> </div> </div> </body> </html> |
