Python django.db.models.lookups.Lookup() Examples
The following are 11
code examples of django.db.models.lookups.Lookup().
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django.db.models.lookups
, or try the search function
.
.
Example #1
| Source File: base.py From wagtail with BSD 3-Clause "New" or "Revised" License | 6 votes |
|
def _process_filter(self, field_attname, lookup, value, check_only=False):
# Get the field
field = self._get_filterable_field(field_attname)
if field is None:
raise FilterFieldError(
'Cannot filter search results with field "' + field_attname + '". Please add index.FilterField(\''
+ field_attname + '\') to ' + self.queryset.model.__name__ + '.search_fields.',
field_name=field_attname
)
# Process the lookup
if not check_only:
result = self._process_lookup(field, lookup, value)
if result is None:
raise FilterError(
'Could not apply filter on search results: "' + field_attname + '__'
+ lookup + ' = ' + str(value) + '". Lookup "' + lookup + '"" not recognised.'
)
return result
Example #2
| Source File: query_utils.py From bioforum with MIT License | 5 votes |
|
def get_lookup(self, lookup_name):
from django.db.models.lookups import Lookup
found = self._get_lookup(lookup_name)
if found is None and hasattr(self, 'output_field'):
return self.output_field.get_lookup(lookup_name)
if found is not None and not issubclass(found, Lookup):
return None
return found
Example #3
| Source File: query_utils.py From Hands-On-Application-Development-with-PyCharm with MIT License | 5 votes |
|
def get_lookup(self, lookup_name):
from django.db.models.lookups import Lookup
found = self._get_lookup(lookup_name)
if found is None and hasattr(self, 'output_field'):
return self.output_field.get_lookup(lookup_name)
if found is not None and not issubclass(found, Lookup):
return None
return found
Example #4
| Source File: base.py From wagtail with BSD 3-Clause "New" or "Revised" License | 5 votes |
|
def _get_filters_from_where_node(self, where_node, check_only=False):
# Check if this is a leaf node
if isinstance(where_node, Lookup):
field_attname = where_node.lhs.target.attname
lookup = where_node.lookup_name
value = where_node.rhs
# Ignore pointer fields that show up in specific page type queries
if field_attname.endswith('_ptr_id'):
return
# Process the filter
return self._process_filter(field_attname, lookup, value, check_only=check_only)
elif isinstance(where_node, SubqueryConstraint):
raise FilterError('Could not apply filter on search results: Subqueries are not allowed.')
elif isinstance(where_node, WhereNode):
# Get child filters
connector = where_node.connector
child_filters = [self._get_filters_from_where_node(child) for child in where_node.children]
if not check_only:
child_filters = [child_filter for child_filter in child_filters if child_filter]
return self._connect_filters(child_filters, connector, where_node.negated)
else:
raise FilterError('Could not apply filter on search results: Unknown where node: ' + str(type(where_node)))
Example #5
| Source File: query_utils.py From python with Apache License 2.0 | 5 votes |
|
def get_lookup(self, lookup_name):
from django.db.models.lookups import Lookup
found = self._get_lookup(lookup_name)
if found is None and hasattr(self, 'output_field'):
return self.output_field.get_lookup(lookup_name)
if found is not None and not issubclass(found, Lookup):
return None
return found
Example #6
| Source File: query_utils.py From openhgsenti with Apache License 2.0 | 5 votes |
|
def get_lookup(self, lookup_name):
from django.db.models.lookups import Lookup
found = self._get_lookup(lookup_name)
if found is None and hasattr(self, 'output_field'):
return self.output_field.get_lookup(lookup_name)
if found is not None and not issubclass(found, Lookup):
return None
return found
Example #7
| Source File: query_utils.py From python2017 with MIT License | 5 votes |
|
def get_lookup(self, lookup_name):
from django.db.models.lookups import Lookup
found = self._get_lookup(lookup_name)
if found is None and hasattr(self, 'output_field'):
return self.output_field.get_lookup(lookup_name)
if found is not None and not issubclass(found, Lookup):
return None
return found
Example #8
| Source File: query.py From bioforum with MIT License | 4 votes |
|
def rewrite_cols(self, annotation, col_cnt):
# We must make sure the inner query has the referred columns in it.
# If we are aggregating over an annotation, then Django uses Ref()
# instances to note this. However, if we are annotating over a column
# of a related model, then it might be that column isn't part of the
# SELECT clause of the inner query, and we must manually make sure
# the column is selected. An example case is:
# .aggregate(Sum('author__awards'))
# Resolving this expression results in a join to author, but there
# is no guarantee the awards column of author is in the select clause
# of the query. Thus we must manually add the column to the inner
# query.
orig_exprs = annotation.get_source_expressions()
new_exprs = []
for expr in orig_exprs:
# FIXME: These conditions are fairly arbitrary. Identify a better
# method of having expressions decide which code path they should
# take.
if isinstance(expr, Ref):
# Its already a Ref to subquery (see resolve_ref() for
# details)
new_exprs.append(expr)
elif isinstance(expr, (WhereNode, Lookup)):
# Decompose the subexpressions further. The code here is
# copied from the else clause, but this condition must appear
# before the contains_aggregate/is_summary condition below.
new_expr, col_cnt = self.rewrite_cols(expr, col_cnt)
new_exprs.append(new_expr)
elif isinstance(expr, Col) or (expr.contains_aggregate and not expr.is_summary):
# Reference to column. Make sure the referenced column
# is selected.
col_cnt += 1
col_alias = '__col%d' % col_cnt
self.annotations[col_alias] = expr
self.append_annotation_mask([col_alias])
new_exprs.append(Ref(col_alias, expr))
else:
# Some other expression not referencing database values
# directly. Its subexpression might contain Cols.
new_expr, col_cnt = self.rewrite_cols(expr, col_cnt)
new_exprs.append(new_expr)
annotation.set_source_expressions(new_exprs)
return annotation, col_cnt
Example #9
| Source File: query.py From Hands-On-Application-Development-with-PyCharm with MIT License | 4 votes |
|
def rewrite_cols(self, annotation, col_cnt):
# We must make sure the inner query has the referred columns in it.
# If we are aggregating over an annotation, then Django uses Ref()
# instances to note this. However, if we are annotating over a column
# of a related model, then it might be that column isn't part of the
# SELECT clause of the inner query, and we must manually make sure
# the column is selected. An example case is:
# .aggregate(Sum('author__awards'))
# Resolving this expression results in a join to author, but there
# is no guarantee the awards column of author is in the select clause
# of the query. Thus we must manually add the column to the inner
# query.
orig_exprs = annotation.get_source_expressions()
new_exprs = []
for expr in orig_exprs:
# FIXME: These conditions are fairly arbitrary. Identify a better
# method of having expressions decide which code path they should
# take.
if isinstance(expr, Ref):
# Its already a Ref to subquery (see resolve_ref() for
# details)
new_exprs.append(expr)
elif isinstance(expr, (WhereNode, Lookup)):
# Decompose the subexpressions further. The code here is
# copied from the else clause, but this condition must appear
# before the contains_aggregate/is_summary condition below.
new_expr, col_cnt = self.rewrite_cols(expr, col_cnt)
new_exprs.append(new_expr)
elif isinstance(expr, Col) or (expr.contains_aggregate and not expr.is_summary):
# Reference to column. Make sure the referenced column
# is selected.
col_cnt += 1
col_alias = '__col%d' % col_cnt
self.annotations[col_alias] = expr
self.append_annotation_mask([col_alias])
new_exprs.append(Ref(col_alias, expr))
else:
# Some other expression not referencing database values
# directly. Its subexpression might contain Cols.
new_expr, col_cnt = self.rewrite_cols(expr, col_cnt)
new_exprs.append(new_expr)
annotation.set_source_expressions(new_exprs)
return annotation, col_cnt
Example #10
| Source File: query.py From python with Apache License 2.0 | 4 votes |
|
def rewrite_cols(self, annotation, col_cnt):
# We must make sure the inner query has the referred columns in it.
# If we are aggregating over an annotation, then Django uses Ref()
# instances to note this. However, if we are annotating over a column
# of a related model, then it might be that column isn't part of the
# SELECT clause of the inner query, and we must manually make sure
# the column is selected. An example case is:
# .aggregate(Sum('author__awards'))
# Resolving this expression results in a join to author, but there
# is no guarantee the awards column of author is in the select clause
# of the query. Thus we must manually add the column to the inner
# query.
orig_exprs = annotation.get_source_expressions()
new_exprs = []
for expr in orig_exprs:
# FIXME: These conditions are fairly arbitrary. Identify a better
# method of having expressions decide which code path they should
# take.
if isinstance(expr, Ref):
# Its already a Ref to subquery (see resolve_ref() for
# details)
new_exprs.append(expr)
elif isinstance(expr, (WhereNode, Lookup)):
# Decompose the subexpressions further. The code here is
# copied from the else clause, but this condition must appear
# before the contains_aggregate/is_summary condition below.
new_expr, col_cnt = self.rewrite_cols(expr, col_cnt)
new_exprs.append(new_expr)
elif isinstance(expr, Col) or (expr.contains_aggregate and not expr.is_summary):
# Reference to column. Make sure the referenced column
# is selected.
col_cnt += 1
col_alias = '__col%d' % col_cnt
self.annotations[col_alias] = expr
self.append_annotation_mask([col_alias])
new_exprs.append(Ref(col_alias, expr))
else:
# Some other expression not referencing database values
# directly. Its subexpression might contain Cols.
new_expr, col_cnt = self.rewrite_cols(expr, col_cnt)
new_exprs.append(new_expr)
annotation.set_source_expressions(new_exprs)
return annotation, col_cnt
Example #11
| Source File: query.py From python2017 with MIT License | 4 votes |
|
def rewrite_cols(self, annotation, col_cnt):
# We must make sure the inner query has the referred columns in it.
# If we are aggregating over an annotation, then Django uses Ref()
# instances to note this. However, if we are annotating over a column
# of a related model, then it might be that column isn't part of the
# SELECT clause of the inner query, and we must manually make sure
# the column is selected. An example case is:
# .aggregate(Sum('author__awards'))
# Resolving this expression results in a join to author, but there
# is no guarantee the awards column of author is in the select clause
# of the query. Thus we must manually add the column to the inner
# query.
orig_exprs = annotation.get_source_expressions()
new_exprs = []
for expr in orig_exprs:
# FIXME: These conditions are fairly arbitrary. Identify a better
# method of having expressions decide which code path they should
# take.
if isinstance(expr, Ref):
# Its already a Ref to subquery (see resolve_ref() for
# details)
new_exprs.append(expr)
elif isinstance(expr, (WhereNode, Lookup)):
# Decompose the subexpressions further. The code here is
# copied from the else clause, but this condition must appear
# before the contains_aggregate/is_summary condition below.
new_expr, col_cnt = self.rewrite_cols(expr, col_cnt)
new_exprs.append(new_expr)
elif isinstance(expr, Col) or (expr.contains_aggregate and not expr.is_summary):
# Reference to column. Make sure the referenced column
# is selected.
col_cnt += 1
col_alias = '__col%d' % col_cnt
self.annotations[col_alias] = expr
self.append_annotation_mask([col_alias])
new_exprs.append(Ref(col_alias, expr))
else:
# Some other expression not referencing database values
# directly. Its subexpression might contain Cols.
new_expr, col_cnt = self.rewrite_cols(expr, col_cnt)
new_exprs.append(new_expr)
annotation.set_source_expressions(new_exprs)
return annotation, col_cnt
