def __set__(self, dbobj, new_values):
self.check_dbobj(dbobj)
if new_values is None:
raise ValueError("You cannot set a sqltuple to None, sorry.")
# Convert each of the values in the new tuple to the
# child_column's type and run its validators on each of them.
new = []
for value in new_values:
value = self.child_column.__convert__(value)
for validator in self.child_column.validators:
validator.check(dbobj, self, value)
new.append(value)
# Let's see if it's just an addition of values. In that case
# we'll not delete anything, just create a couple of INSERT
# statements.
if self.isset(dbobj):
dont_delete = True
old = getattr(dbobj, self.data_attribute_name())
if len(old) <= len(new):
for o, n in zip(old, new):
if o != n:
dont_delete = False
break
else:
old = ()
dont_delete = False
if dont_delete:
to_insert = new[len(old):]
else:
to_insert = new
dbobj.__ds__().execute(sql.delete(self.child_relation,
self.child_where(dbobj)))
for value in to_insert:
if value is None:
literal = sql.NULL
else:
literal = self.child_column.sql_literal_class(value)
dbobj.__ds__().execute(
sql.insert(self.child_relation,
( self.child_key,
self.child_column.column, ),
( dbobj.__primary_key__.sql_literal(),
literal, ) ))
setattr(dbobj, self.data_attribute_name(), tuple(new))
def __delitem__(self, key):
key_column = self._sqldict.child_key_column.column
key_literal = self._sqldict.child_key_column.sql_literal_class(key)
where = self.child_where(dbobj) + sql.where(
key_column, " = ", key_literal)
dbobj.__ds__().execute(sql.delete(self.child_relation, where))
dict.__delitem__(self, key)
def __set__(self, dbobj, value):
# make sure value is a sequence.
try:
value = list(value)
except TypeError:
raise ValueError( ("You must assing a sequence of %s to this "
"dbproperty!") % repr(self.child_class))
# delete all links from the link_relation that point to the dbobj
command = sql.delete(self.link_relation,
sql.where(self.parent_link_column(dbobj),
" = ",
dbobj.__primary_key__.sql_literal()))
dbobj.__ds__().execute(command)
# use the result class to (re-)insert the links
result = self.result(dbobj, self)
result.append(*value)
def unlink_by_primary_key(self, pkey):
"""
Remove an entry from the link relation that links the parent
dbobj to a child identfyed by pkey
@param pkey: An sql.literal instance
"""
if not isinstance(pkey, sql.literal):
raise TypeError("pkey must be an sql.literal instance!")
cmd = sql.delete(self.relationship.link_relation,
sql.where(self.relationship.parent_link_column(self.dbobj),
" = ",
self.dbobj.__primary_key__.sql_literal(),
" AND ",
self.relationship.child_link_column(),
" = ",
pkey))
self.ds().execute(cmd)
def __delete__(self):
cmd = sql.delete(self.__relation__, self.__primary_key__.where())
self.__ds__().execute(cmd)
def __set__(self, dbobj, new_dict):
if new_dict is None:
raise ValueError("You cannot set a sqldict to None, sorry.")
self.check_dbobj(dbobj)
if self.isset(dbobj):
# We have a new version of the dict in memory and can compare
# values against it.
old_dict = getattr(dbobj, self.data_attribute_name())
old_dict.update(new_dict)
new_keys = set(new_dict.keys())
old_keys = set(old_dict.keys())
obsolete_keys = old_keys.difference(new_keys)
for key in obsolete_keys:
old_dict[key]
else:
if dbobj.__ds__():
raise ValueError("Can’t initialize a sqldict on "
"dbobject creation, only after insert().")
# Convert each of the keys and values in the new dict to the
# appropriate types and run the validators on each of the values.
new = {}
for key, value in new_dict.items():
key = self.child_key_column.__convert__(key)
value = self.child_value_column.__convert__(value)
for validator in self.child_key_column.validators:
validator.check(dbobj, self, key)
for validator in self.child_value_column.validators:
validator.check(dbobj, self, value)
new[key] = value
# Delete the rows currently in the database
dbobj.__ds__().execute(sql.delete(self.child_relation,
self.child_where(dbobj)))
# And insert new ones
for key, value in new.items():
key_literal = self.child_key_column.sql_literal_class(
self.child_key_column.__convert__(key))
if value is None:
value_literal = sql.NULL
else:
value_literal = self.child_value_column.sql_literal_class(
self.child_value_column.__convert__(value))
query = sql.insert( self.child_relation,
( self.child_key,
self.child_key_column.column,
self.child_value_column.column, ),
( dbobj.__primary_key__.sql_literal(),
key_literal, value_literal, ) )
dbobj.__ds__().execute(query)
setattr(dbobj, self.data_attribute_name(),
self.sqldict_dict(self, dbobj, new))
def delete(self, dbclass, where, cursor=None):
command = sql.delete(dbclass.__relation__, where)
self.execute(command, cursor)
