Python django.db.models.expressions.Col() Examples
The following are 24
code examples of django.db.models.expressions.Col().
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django.db.models.expressions
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Example #1
| Source File: lookups.py From GTDWeb with GNU General Public License v2.0 | 6 votes |
|
def process_rhs(self, compiler, connection):
rhs, rhs_params = super(GISLookup, self).process_rhs(compiler, connection)
if hasattr(self.rhs, '_as_sql'):
# If rhs is some QuerySet, don't touch it
return rhs, rhs_params
geom = self.rhs
if isinstance(self.rhs, Col):
# Make sure the F Expression destination field exists, and
# set an `srid` attribute with the same as that of the
# destination.
geo_fld = self.rhs.output_field
if not hasattr(geo_fld, 'srid'):
raise ValueError('No geographic field found in expression.')
self.rhs.srid = geo_fld.srid
elif isinstance(self.rhs, Expression):
raise ValueError('Complex expressions not supported for GeometryField')
elif isinstance(self.rhs, (list, tuple)):
geom = self.rhs[0]
rhs = connection.ops.get_geom_placeholder(self.lhs.output_field, geom, compiler)
return rhs, rhs_params
Example #2
| Source File: operations.py From bioforum with MIT License | 6 votes |
|
def get_db_converters(self, expression):
converters = super().get_db_converters(expression)
internal_type = expression.output_field.get_internal_type()
if internal_type == 'DateTimeField':
converters.append(self.convert_datetimefield_value)
elif internal_type == 'DateField':
converters.append(self.convert_datefield_value)
elif internal_type == 'TimeField':
converters.append(self.convert_timefield_value)
# Converter for Col is added with Database.register_converter()
# in base.py.
elif internal_type == 'DecimalField' and not isinstance(expression, Col):
converters.append(self.convert_decimalfield_value)
elif internal_type == 'UUIDField':
converters.append(self.convert_uuidfield_value)
elif internal_type in ('NullBooleanField', 'BooleanField'):
converters.append(self.convert_booleanfield_value)
return converters
Example #3
| Source File: lookups.py From openhgsenti with Apache License 2.0 | 6 votes |
|
def process_rhs(self, compiler, connection):
rhs, rhs_params = super(GISLookup, self).process_rhs(compiler, connection)
if hasattr(self.rhs, '_as_sql'):
# If rhs is some QuerySet, don't touch it
return rhs, rhs_params
geom = self.rhs
if isinstance(self.rhs, Col):
# Make sure the F Expression destination field exists, and
# set an `srid` attribute with the same as that of the
# destination.
geo_fld = self.rhs.output_field
if not hasattr(geo_fld, 'srid'):
raise ValueError('No geographic field found in expression.')
self.rhs.srid = geo_fld.srid
elif isinstance(self.rhs, Expression):
raise ValueError('Complex expressions not supported for GeometryField')
elif isinstance(self.rhs, (list, tuple)):
geom = self.rhs[0]
rhs = connection.ops.get_geom_placeholder(self.lhs.output_field, geom, compiler)
return rhs, rhs_params
Example #4
| Source File: __init__.py From Hands-On-Application-Development-with-PyCharm with MIT License | 5 votes |
|
def cached_col(self):
from django.db.models.expressions import Col
return Col(self.model._meta.db_table, self)
Example #5
| Source File: query.py From django-partial-index with BSD 3-Clause "New" or "Revised" License | 5 votes |
|
def expression_mentioned_fields(exp):
if isinstance(exp, expressions.Col):
field = exp.output_field or exp.field # TODO: which one makes sense to use here?
if field and field.name:
return [field.name]
elif hasattr(exp, 'get_source_expressions'):
child_fields = []
for source in exp.get_source_expressions():
child_fields.extend(expression_mentioned_fields(source))
return child_fields
else:
raise NotImplementedError('Unexpected expression class %s=%s when looking up mentioned fields.' % (exp.__class__.__name__, exp))
Example #6
| Source File: __init__.py From python2017 with MIT License | 5 votes |
|
def cached_col(self):
from django.db.models.expressions import Col
return Col(self.model._meta.db_table, self)
Example #7
| Source File: __init__.py From python2017 with MIT License | 5 votes |
|
def get_col(self, alias, output_field=None):
if output_field is None:
output_field = self
if alias != self.model._meta.db_table or output_field != self:
from django.db.models.expressions import Col
return Col(alias, self, output_field)
else:
return self.cached_col
Example #8
| Source File: __init__.py From openhgsenti with Apache License 2.0 | 5 votes |
|
def cached_col(self):
from django.db.models.expressions import Col
return Col(self.model._meta.db_table, self)
Example #9
| Source File: __init__.py From openhgsenti with Apache License 2.0 | 5 votes |
|
def get_col(self, alias, output_field=None):
if output_field is None:
output_field = self
if alias != self.model._meta.db_table or output_field != self:
from django.db.models.expressions import Col
return Col(alias, self, output_field)
else:
return self.cached_col
Example #10
| Source File: query.py From openhgsenti with Apache License 2.0 | 5 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:
if isinstance(expr, Ref):
# Its already a Ref to subquery (see resolve_ref() for
# details)
new_exprs.append(expr)
elif isinstance(expr, Col):
# 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: __init__.py From python with Apache License 2.0 | 5 votes |
|
def cached_col(self):
from django.db.models.expressions import Col
return Col(self.model._meta.db_table, self)
Example #12
| Source File: __init__.py From python with Apache License 2.0 | 5 votes |
|
def get_col(self, alias, output_field=None):
if output_field is None:
output_field = self
if alias != self.model._meta.db_table or output_field != self:
from django.db.models.expressions import Col
return Col(alias, self, output_field)
else:
return self.cached_col
Example #13
| Source File: query.py From GTDWeb with GNU General Public License v2.0 | 5 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:
if isinstance(expr, Ref):
# Its already a Ref to subquery (see resolve_ref() for
# details)
new_exprs.append(expr)
elif isinstance(expr, Col):
# 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 #14
| Source File: __init__.py From Hands-On-Application-Development-with-PyCharm with MIT License | 5 votes |
|
def get_col(self, alias, output_field=None):
if output_field is None:
output_field = self
if alias != self.model._meta.db_table or output_field != self:
from django.db.models.expressions import Col
return Col(alias, self, output_field)
else:
return self.cached_col
Example #15
| Source File: operations.py From Hands-On-Application-Development-with-PyCharm with MIT License | 5 votes |
|
def get_decimalfield_converter(self, expression):
# SQLite stores only 15 significant digits. Digits coming from
# float inaccuracy must be removed.
create_decimal = decimal.Context(prec=15).create_decimal_from_float
if isinstance(expression, Col):
quantize_value = decimal.Decimal(1).scaleb(-expression.output_field.decimal_places)
def converter(value, expression, connection):
if value is not None:
return create_decimal(value).quantize(quantize_value, context=expression.output_field.context)
else:
def converter(value, expression, connection):
if value is not None:
return create_decimal(value)
return converter
Example #16
| Source File: lookups.py From django-localized-fields with MIT License | 5 votes |
|
def process_lhs(self, qn, connection):
if isinstance(self.lhs, Col):
language = translation.get_language() or settings.LANGUAGE_CODE
self.lhs = KeyTransform(language, self.lhs)
return super().process_lhs(qn, connection)
Example #17
| Source File: __init__.py From bioforum with MIT License | 5 votes |
|
def cached_col(self):
from django.db.models.expressions import Col
return Col(self.model._meta.db_table, self)
Example #18
| Source File: __init__.py From bioforum with MIT License | 5 votes |
|
def get_col(self, alias, output_field=None):
if output_field is None:
output_field = self
if alias != self.model._meta.db_table or output_field != self:
from django.db.models.expressions import Col
return Col(alias, self, output_field)
else:
return self.cached_col
Example #19
| Source File: __init__.py From GTDWeb with GNU General Public License v2.0 | 5 votes |
|
def cached_col(self):
from django.db.models.expressions import Col
return Col(self.model._meta.db_table, self)
Example #20
| Source File: __init__.py From GTDWeb with GNU General Public License v2.0 | 5 votes |
|
def get_col(self, alias, output_field=None):
if output_field is None:
output_field = self
if alias != self.model._meta.db_table or output_field != self:
from django.db.models.expressions import Col
return Col(alias, self, output_field)
else:
return self.cached_col
Example #21
| 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 #22
| 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 #23
| 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
Example #24
| 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
