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Code Issues 32 Releases Wiki Activity

queyrset-refactor: Some more speed-ups due to datastructure changes.

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git-svn-id: http://code.djangoproject.com/svn/django/branches/queryset-refactor@7255 bcc190cf-cafb-0310-a4f2-bffc1f526a37
This commit is contained in:
Malcolm Tredinnick 2008-03-17 13:32:11 +00:00
parent 067d380e98
commit 133111e40b
3 changed files with 111 additions and 120 deletions
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6
django/db/models/fields/related.py
View File

@ -530,7 +530,11 @@ class ManyToOneRel(object):
Returns the Field in the 'to' object to which this relationship is Returns the Field in the 'to' object to which this relationship is
tied. tied.
""" """
return self.to._meta.get_field_by_name(self.field_name, True)[0] data = self.to._meta.get_field_by_name(self.field_name)
if not data[2]:
raise FieldDoesNotExist("No related field named '%s'" %
self.field_name)
return data[0]
class OneToOneRel(ManyToOneRel): class OneToOneRel(ManyToOneRel):
def __init__(self, to, field_name, num_in_admin=0, min_num_in_admin=None, def __init__(self, to, field_name, num_in_admin=0, min_num_in_admin=None,

14
django/db/models/options.py
View File

@ -231,7 +231,7 @@ class Options(object):
return f return f
raise FieldDoesNotExist, '%s has no field named %r' % (self.object_name, name) raise FieldDoesNotExist, '%s has no field named %r' % (self.object_name, name)
def get_field_by_name(self, name, only_direct=False): def get_field_by_name(self, name):
""" """
Returns the (field_object, model, direct, m2m), where field_object is Returns the (field_object, model, direct, m2m), where field_object is
the Field instance for the given name, model is the model containing the Field instance for the given name, model is the model containing
@ -241,21 +241,17 @@ class Options(object):
for this field (since the field doesn't have an instance associated for this field (since the field doesn't have an instance associated
with it). with it).
If 'only_direct' is True, only forwards relations (and non-relations)
are considered in the result.
Uses a cache internally, so after the first access, this is very fast. Uses a cache internally, so after the first access, this is very fast.
""" """
try: try:
result = self._name_map.get(name) try:
return self._name_map[name]
except AttributeError: except AttributeError:
cache = self.init_name_map() cache = self.init_name_map()
result = cache.get(name) return self._name_map[name]
except KeyError:
if not result or (only_direct and not result[2]):
raise FieldDoesNotExist('%s has no field named %r' raise FieldDoesNotExist('%s has no field named %r'
% (self.object_name, name)) % (self.object_name, name))
return result
def get_all_field_names(self): def get_all_field_names(self):
""" """

169
django/db/models/sql/query.py
View File

@ -46,7 +46,8 @@ class Query(object):
self.alias_refcount = {} self.alias_refcount = {}
self.alias_map = {} # Maps alias to join information self.alias_map = {} # Maps alias to join information
self.table_map = {} # Maps table names to list of aliases. self.table_map = {} # Maps table names to list of aliases.
self.rev_join_map = {} # Reverse of join_map. (FIXME: Update comment) self.join_map = {}
self.rev_join_map = {} # Reverse of join_map.
self.quote_cache = {} self.quote_cache = {}
self.default_cols = True self.default_cols = True
self.default_ordering = True self.default_ordering = True
@ -130,6 +131,7 @@ class Query(object):
obj.alias_refcount = self.alias_refcount.copy() obj.alias_refcount = self.alias_refcount.copy()
obj.alias_map = self.alias_map.copy() obj.alias_map = self.alias_map.copy()
obj.table_map = self.table_map.copy() obj.table_map = self.table_map.copy()
obj.join_map = self.join_map.copy()
obj.rev_join_map = self.rev_join_map.copy() obj.rev_join_map = self.rev_join_map.copy()
obj.quote_cache = {} obj.quote_cache = {}
obj.default_cols = self.default_cols obj.default_cols = self.default_cols
@ -271,7 +273,7 @@ class Query(object):
# Work out how to relabel the rhs aliases, if necessary. # Work out how to relabel the rhs aliases, if necessary.
change_map = {} change_map = {}
used = {} used = set()
conjunction = (connector == AND) conjunction = (connector == AND)
first = True first = True
for alias in rhs.tables: for alias in rhs.tables:
@ -281,7 +283,7 @@ class Query(object):
promote = (rhs.alias_map[alias][JOIN_TYPE] == self.LOUTER) promote = (rhs.alias_map[alias][JOIN_TYPE] == self.LOUTER)
new_alias = self.join(rhs.rev_join_map[alias], new_alias = self.join(rhs.rev_join_map[alias],
(conjunction and not first), used, promote, not conjunction) (conjunction and not first), used, promote, not conjunction)
used[new_alias] = None used.add(new_alias)
change_map[alias] = new_alias change_map[alias] = new_alias
first = False first = False
@ -411,22 +413,17 @@ class Query(object):
""" """
result = [] result = []
qn = self.quote_name_unless_alias qn = self.quote_name_unless_alias
qn2 = self.connection.ops.quote_name
first = True first = True
for alias in self.tables: for alias in self.tables:
if not self.alias_refcount[alias]: if not self.alias_refcount[alias]:
continue continue
join = self.alias_map[alias] name, alias, join_type, lhs, lhs_col, col, nullable = self.alias_map[alias]
if join:
name, alias, join_type, lhs, lhs_col, col, nullable = join
alias_str = (alias != name and ' AS %s' % alias or '') alias_str = (alias != name and ' AS %s' % alias or '')
else:
join_type = None
alias_str = ''
name = alias
if join_type and not first: if join_type and not first:
result.append('%s %s%s ON (%s.%s = %s.%s)' result.append('%s %s%s ON (%s.%s = %s.%s)'
% (join_type, qn(name), alias_str, qn(lhs), % (join_type, qn(name), alias_str, qn(lhs),
qn(lhs_col), qn(alias), qn(col))) qn2(lhs_col), qn(alias), qn2(col)))
else: else:
connector = not first and ', ' or '' connector = not first and ', ' or ''
result.append('%s%s%s' % (connector, qn(name), alias_str)) result.append('%s%s%s' % (connector, qn(name), alias_str))
@ -472,6 +469,7 @@ class Query(object):
else: else:
ordering = self.order_by or self.model._meta.ordering ordering = self.order_by or self.model._meta.ordering
qn = self.quote_name_unless_alias qn = self.quote_name_unless_alias
qn2 = self.connection.ops.quote_name
distinct = self.distinct distinct = self.distinct
select_aliases = self._select_aliases select_aliases = self._select_aliases
result = [] result = []
@ -492,12 +490,11 @@ class Query(object):
result.append('%s %s' % (field, order)) result.append('%s %s' % (field, order))
continue continue
if '.' in field: if '.' in field:
# This came in through an extra(ordering=...) addition. Pass it # This came in through an extra(order_by=...) addition. Pass it
# on verbatim, after mapping the table name to an alias, if # on verbatim.
# necessary.
col, order = get_order_dir(field, asc) col, order = get_order_dir(field, asc)
table, col = col.split('.', 1) table, col = col.split('.', 1)
elt = '%s.%s' % (qn(self.table_alias(table)[0]), col) elt = '%s.%s' % (qn(table), col)
if not distinct or elt in select_aliases: if not distinct or elt in select_aliases:
result.append('%s %s' % (elt, order)) result.append('%s %s' % (elt, order))
elif get_order_dir(field)[0] not in self.extra_select: elif get_order_dir(field)[0] not in self.extra_select:
@ -505,7 +502,7 @@ class Query(object):
# '-field1__field2__field', etc. # '-field1__field2__field', etc.
for table, col, order in self.find_ordering_name(field, for table, col, order in self.find_ordering_name(field,
self.model._meta, default_order=asc): self.model._meta, default_order=asc):
elt = '%s.%s' % (qn(table), qn(col)) elt = '%s.%s' % (qn(table), qn2(col))
if not distinct or elt in select_aliases: if not distinct or elt in select_aliases:
result.append('%s %s' % (elt, order)) result.append('%s %s' % (elt, order))
else: else:
@ -527,11 +524,11 @@ class Query(object):
if not alias: if not alias:
alias = self.get_initial_alias() alias = self.get_initial_alias()
try: try:
field, target, opts, joins = self.setup_joins(pieces, opts, alias, field, target, opts, joins, last = self.setup_joins(pieces, opts,
False, False) alias, False, False)
except JoinError: except JoinError:
raise FieldError("Cannot order by many-valued field: '%s'" % name) raise FieldError("Cannot order by many-valued field: '%s'" % name)
alias = joins[-1][-1] alias = joins[-1]
col = target.column col = target.column
# If we get to this point and the field is a relation to another model, # If we get to this point and the field is a relation to another model,
@ -540,7 +537,7 @@ class Query(object):
# Firstly, avoid infinite loops. # Firstly, avoid infinite loops.
if not already_seen: if not already_seen:
already_seen = set() already_seen = set()
join_tuple = tuple([tuple(j) for j in joins]) join_tuple = tuple(joins)
if join_tuple in already_seen: if join_tuple in already_seen:
raise FieldError('Infinite loop caused by ordering.') raise FieldError('Infinite loop caused by ordering.')
already_seen.add(join_tuple) already_seen.add(join_tuple)
@ -570,20 +567,22 @@ class Query(object):
If 'create' is true, a new alias is always created. Otherwise, the If 'create' is true, a new alias is always created. Otherwise, the
most recently created alias for the table (if one exists) is reused. most recently created alias for the table (if one exists) is reused.
""" """
if not create and table_name in self.table_map: current = self.table_map.get(table_name)
alias = self.table_map[table_name][-1] if not create and current:
alias = current[0]
self.alias_refcount[alias] += 1 self.alias_refcount[alias] += 1
return alias, False return alias, False
# Create a new alias for this table. # Create a new alias for this table.
if table_name not in self.table_map: if current:
alias = '%s%d' % (self.alias_prefix, len(self.alias_map) + 1)
current.append(alias)
else:
# The first occurence of a table uses the table name directly. # The first occurence of a table uses the table name directly.
alias = table_name alias = table_name
else: self.table_map[alias] = [alias]
alias = '%s%d' % (self.alias_prefix, len(self.alias_map) + 1)
self.alias_refcount[alias] = 1 self.alias_refcount[alias] = 1
self.alias_map[alias] = None #self.alias_map[alias] = None
self.table_map.setdefault(table_name, []).append(alias)
self.tables.append(alias) self.tables.append(alias)
return alias, True return alias, True
@ -629,7 +628,9 @@ class Query(object):
alias_data = list(self.alias_map[old_alias]) alias_data = list(self.alias_map[old_alias])
alias_data[RHS_ALIAS] = new_alias alias_data[RHS_ALIAS] = new_alias
self.rev_join_map[new_alias] = self.rev_join_map[old_alias] t = self.rev_join_map[old_alias]
self.join_map[t] = new_alias
self.rev_join_map[new_alias] = t
del self.rev_join_map[old_alias] del self.rev_join_map[old_alias]
self.alias_refcount[new_alias] = self.alias_refcount[old_alias] self.alias_refcount[new_alias] = self.alias_refcount[old_alias]
del self.alias_refcount[old_alias] del self.alias_refcount[old_alias]
@ -654,7 +655,6 @@ class Query(object):
data[LHS_ALIAS] = change_map[lhs] data[LHS_ALIAS] = change_map[lhs]
self.alias_map[alias] = tuple(data) self.alias_map[alias] = tuple(data)
def bump_prefix(self): def bump_prefix(self):
""" """
Changes the alias prefix to the next letter in the alphabet and Changes the alias prefix to the next letter in the alphabet and
@ -724,29 +724,19 @@ class Query(object):
is a candidate for promotion (to "left outer") when combining querysets. is a candidate for promotion (to "left outer") when combining querysets.
""" """
lhs, table, lhs_col, col = connection lhs, table, lhs_col, col = connection
if lhs is None: if lhs in self.alias_map:
lhs_table = None
is_table = False
elif lhs not in self.alias_map:
lhs_table = lhs
is_table = True
else:
lhs_table = self.alias_map[lhs][TABLE_NAME] lhs_table = self.alias_map[lhs][TABLE_NAME]
is_table = False else:
lhs_table = lhs
t_ident = (lhs_table, table, lhs_col, col) t_ident = (lhs_table, table, lhs_col, col)
if not always_create: alias = self.join_map.get(t_ident)
for alias, row in self.rev_join_map.items(): if alias and not always_create and alias not in exclusions:
if t_ident == row and alias not in exclusions:
self.ref_alias(alias) self.ref_alias(alias)
if promote: if promote:
self.promote_alias(alias) self.promote_alias(alias)
return alias return alias
# If we get to here (no non-excluded alias exists), we'll fall
# through to creating a new alias.
# No reuse is possible, so we need a new alias. # No reuse is possible, so we need a new alias.
assert not is_table, \
"Must pass in lhs alias when creating a new join."
alias, _ = self.table_alias(table, True) alias, _ = self.table_alias(table, True)
if not lhs: if not lhs:
# Not all tables need to be joined to anything. No join type # Not all tables need to be joined to anything. No join type
@ -758,6 +748,7 @@ class Query(object):
join_type = self.INNER join_type = self.INNER
join = (table, alias, join_type, lhs, lhs_col, col, nullable) join = (table, alias, join_type, lhs, lhs_col, col, nullable)
self.alias_map[alias] = join self.alias_map[alias] = join
self.join_map[t_ident] = alias
self.rev_join_map[alias] = t_ident self.rev_join_map[alias] = t_ident
return alias return alias
@ -855,22 +846,28 @@ class Query(object):
allow_many = trim or not negate allow_many = trim or not negate
try: try:
field, target, opts, join_list = self.setup_joins(parts, opts, field, target, opts, join_list, last = self.setup_joins(parts, opts,
alias, (connector == AND), allow_many) alias, (connector == AND), allow_many)
except JoinError, e: except JoinError, e:
self.split_exclude(filter_expr, LOOKUP_SEP.join(parts[:e.level])) self.split_exclude(filter_expr, LOOKUP_SEP.join(parts[:e.level]))
return return
final = len(join_list)
penultimate = last.pop()
if penultimate == final:
penultimate = last.pop()
if trim and len(join_list) > 1: if trim and len(join_list) > 1:
extra = join_list[-1] extra = join_list[penultimate:]
join_list = join_list[:-1] join_list = join_list[:penultimate]
final = penultimate
penultimate = last.pop()
col = self.alias_map[extra[0]][LHS_JOIN_COL] col = self.alias_map[extra[0]][LHS_JOIN_COL]
for alias in extra: for alias in extra:
self.unref_alias(alias) self.unref_alias(alias)
else: else:
col = target.column col = target.column
alias = join_list[-1][-1] alias = join_list[-1]
if join_list: if final > 1:
# An optimization: if the final join is against the same column as # An optimization: if the final join is against the same column as
# we are comparing against, we can go back one step in the join # we are comparing against, we can go back one step in the join
# chain and compare against the lhs of the join instead. The result # chain and compare against the lhs of the join instead. The result
@ -880,18 +877,18 @@ class Query(object):
self.unref_alias(alias) self.unref_alias(alias)
alias = join[LHS_ALIAS] alias = join[LHS_ALIAS]
col = join[LHS_JOIN_COL] col = join[LHS_JOIN_COL]
if len(join_list[-1]) == 1:
join_list = join_list[:-1] join_list = join_list[:-1]
else: final -= 1
join_list[-1] = join_list[-1][:-1] if final == penultimate:
penultimate = last.pop()
if (lookup_type == 'isnull' and value is True and not negate and if (lookup_type == 'isnull' and value is True and not negate and
(len(join_list) > 1 or len(join_list[0]) > 1)): final > 1):
# If the comparison is against NULL, we need to use a left outer # If the comparison is against NULL, we need to use a left outer
# join when connecting to the previous model. We make that # join when connecting to the previous model. We make that
# adjustment here. We don't do this unless needed as it's less # adjustment here. We don't do this unless needed as it's less
# efficient at the database level. # efficient at the database level.
self.promote_alias(join_list[-1][0]) self.promote_alias(join_list[penultimate])
if connector == OR: if connector == OR:
# Some joins may need to be promoted when adding a new filter to a # Some joins may need to be promoted when adding a new filter to a
@ -899,7 +896,7 @@ class Query(object):
# from any previous joins (ref count is 1 in the table list), we # from any previous joins (ref count is 1 in the table list), we
# make the new additions (and any existing ones not used in the new # make the new additions (and any existing ones not used in the new
# join list) an outer join. # join list) an outer join.
join_it = itertools.chain(*join_list) join_it = iter(join_list)
table_it = iter(self.tables) table_it = iter(self.tables)
join_it.next(), table_it.next() join_it.next(), table_it.next()
for join in join_it: for join in join_it:
@ -931,14 +928,11 @@ class Query(object):
merged = False merged = False
if negate: if negate:
count = 0 for alias in join_list:
for join in join_list:
count += len(join)
for alias in join:
self.promote_alias(alias) self.promote_alias(alias)
if not merged: if not merged:
self.where.negate() self.where.negate()
if count > 1 and lookup_type != 'isnull': if final > 1 and lookup_type != 'isnull':
j_col = self.alias_map[alias][RHS_JOIN_COL] j_col = self.alias_map[alias][RHS_JOIN_COL]
entry = Node([(alias, j_col, None, 'isnull', True)]) entry = Node([(alias, j_col, None, 'isnull', True)])
entry.negate() entry.negate()
@ -989,10 +983,10 @@ class Query(object):
column (used for any 'where' constraint), the final 'opts' value and the column (used for any 'where' constraint), the final 'opts' value and the
list of tables joined. list of tables joined.
""" """
joins = [[alias]] joins = [alias]
used = set() last = [0]
for pos, name in enumerate(names): for pos, name in enumerate(names):
used.update(joins[-1]) last.append(len(joins))
if name == 'pk': if name == 'pk':
name = opts.pk.name name = opts.pk.name
@ -1011,8 +1005,7 @@ class Query(object):
raise FieldError("Cannot resolve keyword %r into field. " raise FieldError("Cannot resolve keyword %r into field. "
"Choices are: %s" % (name, ", ".join(names))) "Choices are: %s" % (name, ", ".join(names)))
if not allow_many and (m2m or not direct): if not allow_many and (m2m or not direct):
for join in joins: for alias in joins:
for alias in join:
self.unref_alias(alias) self.unref_alias(alias)
raise JoinError(pos + 1) raise JoinError(pos + 1)
if model: if model:
@ -1022,9 +1015,8 @@ class Query(object):
lhs_col = opts.parents[int_model].column lhs_col = opts.parents[int_model].column
opts = int_model._meta opts = int_model._meta
alias = self.join((alias, opts.db_table, lhs_col, alias = self.join((alias, opts.db_table, lhs_col,
opts.pk.column), exclusions=used) opts.pk.column), exclusions=joins)
alias_list.append(alias) joins.append(alias)
joins.append(alias_list)
cached_data = opts._join_cache.get(name) cached_data = opts._join_cache.get(name)
orig_opts = opts orig_opts = opts
@ -1048,10 +1040,10 @@ class Query(object):
target) target)
int_alias = self.join((alias, table1, from_col1, to_col1), int_alias = self.join((alias, table1, from_col1, to_col1),
dupe_multis, used, nullable=True) dupe_multis, joins, nullable=True)
alias = self.join((int_alias, table2, from_col2, to_col2), alias = self.join((int_alias, table2, from_col2, to_col2),
dupe_multis, used, nullable=True) dupe_multis, joins, nullable=True)
joins.append([int_alias, alias]) joins.extend([int_alias, alias])
elif field.rel: elif field.rel:
# One-to-one or many-to-one field # One-to-one or many-to-one field
if cached_data: if cached_data:
@ -1066,8 +1058,8 @@ class Query(object):
opts, target) opts, target)
alias = self.join((alias, table, from_col, to_col), alias = self.join((alias, table, from_col, to_col),
exclusions=used, nullable=field.null) exclusions=joins, nullable=field.null)
joins.append([alias]) joins.append(alias)
else: else:
# Non-relation fields. # Non-relation fields.
target = field target = field
@ -1094,10 +1086,10 @@ class Query(object):
target) target)
int_alias = self.join((alias, table1, from_col1, to_col1), int_alias = self.join((alias, table1, from_col1, to_col1),
dupe_multis, used, nullable=True) dupe_multis, joins, nullable=True)
alias = self.join((int_alias, table2, from_col2, to_col2), alias = self.join((int_alias, table2, from_col2, to_col2),
dupe_multis, used, nullable=True) dupe_multis, joins, nullable=True)
joins.append([int_alias, alias]) joins.extend([int_alias, alias])
else: else:
# One-to-many field (ForeignKey defined on the target model) # One-to-many field (ForeignKey defined on the target model)
if cached_data: if cached_data:
@ -1114,13 +1106,13 @@ class Query(object):
opts, target) opts, target)
alias = self.join((alias, table, from_col, to_col), alias = self.join((alias, table, from_col, to_col),
dupe_multis, used, nullable=True) dupe_multis, joins, nullable=True)
joins.append([alias]) joins.append(alias)
if pos != len(names) - 1: if pos != len(names) - 1:
raise FieldError("Join on field %r not permitted." % name) raise FieldError("Join on field %r not permitted." % name)
return field, target, opts, joins return field, target, opts, joins, last
def split_exclude(self, filter_expr, prefix): def split_exclude(self, filter_expr, prefix):
""" """
@ -1179,9 +1171,10 @@ class Query(object):
opts = self.get_meta() opts = self.get_meta()
try: try:
for name in field_names: for name in field_names:
u1, target, u2, joins = self.setup_joins(name.split(LOOKUP_SEP), u1, target, u2, joins, u3 = self.setup_joins(
opts, alias, False, allow_m2m, True) name.split(LOOKUP_SEP), opts, alias, False, allow_m2m,
self.select.append((joins[-1][-1], target.column)) True)
self.select.append((joins[-1], target.column))
except JoinError: except JoinError:
raise FieldError("Invalid field name: '%s'" % name) raise FieldError("Invalid field name: '%s'" % name)
@ -1294,20 +1287,18 @@ class Query(object):
""" """
opts = self.model._meta opts = self.model._meta
alias = self.get_initial_alias() alias = self.get_initial_alias()
field, col, opts, joins = self.setup_joins(start.split(LOOKUP_SEP), field, col, opts, joins, last = self.setup_joins(
opts, alias, False) start.split(LOOKUP_SEP), opts, alias, False)
alias = joins[-1][0] alias = joins[last[-1]]
self.select = [(alias, self.alias_map[alias][RHS_JOIN_COL])] self.select = [(alias, self.alias_map[alias][RHS_JOIN_COL])]
self.start_meta = opts self.start_meta = opts
# The call to setup_joins add an extra reference to everything in # The call to setup_joins add an extra reference to everything in
# joins. So we need to unref everything once, and everything prior to # joins. So we need to unref everything once, and everything prior to
# the final join a second time. # the final join a second time.
for join in joins[:-1]: for alias in joins:
for alias in join:
self.unref_alias(alias) self.unref_alias(alias)
self.unref_alias(alias) for alias in joins[:last[-1]]:
for alias in joins[-1]:
self.unref_alias(alias) self.unref_alias(alias)
def execute_sql(self, result_type=MULTI): def execute_sql(self, result_type=MULTI):