def check_expression_support(self, expression):
bad_fields = (fields.DateField, fields.DateTimeField, fields.TimeField)
bad_aggregates = (aggregates.Sum, aggregates.Avg, aggregates.Variance, aggregates.StdDev)
if isinstance(expression, bad_aggregates):
for expr in expression.get_source_expressions():
try:
output_field = expr.output_field
if isinstance(output_field, bad_fields):
raise NotImplementedError(
'You cannot use Sum, Avg, StdDev, and Variance '
'aggregations on date/time fields in sqlite3 '
'since date/time is saved as text.'
)
except FieldError:
# Not every subexpression has an output_field which is fine
# to ignore.
pass
python类Variance()的实例源码
def check_expression_support(self, expression):
bad_fields = (fields.DateField, fields.DateTimeField, fields.TimeField)
bad_aggregates = (aggregates.Sum, aggregates.Avg, aggregates.Variance, aggregates.StdDev)
if isinstance(expression, bad_aggregates):
for expr in expression.get_source_expressions():
try:
output_field = expr.output_field
if isinstance(output_field, bad_fields):
raise NotImplementedError(
'You cannot use Sum, Avg, StdDev, and Variance '
'aggregations on date/time fields in sqlite3 '
'since date/time is saved as text.'
)
except FieldError:
# Not every subexpression has an output_field which is fine
# to ignore.
pass
def check_expression_support(self, expression):
bad_fields = (fields.DateField, fields.DateTimeField, fields.TimeField)
bad_aggregates = (aggregates.Sum, aggregates.Avg, aggregates.Variance, aggregates.StdDev)
if isinstance(expression, bad_aggregates):
for expr in expression.get_source_expressions():
try:
output_field = expr.output_field
if isinstance(output_field, bad_fields):
raise NotImplementedError(
'You cannot use Sum, Avg, StdDev, and Variance '
'aggregations on date/time fields in sqlite3 '
'since date/time is saved as text.'
)
except FieldError:
# Not every subexpression has an output_field which is fine
# to ignore.
pass
def check_expression_support(self, expression):
bad_fields = (fields.DateField, fields.DateTimeField, fields.TimeField)
bad_aggregates = (aggregates.Sum, aggregates.Avg, aggregates.Variance, aggregates.StdDev)
if isinstance(expression, bad_aggregates):
for expr in expression.get_source_expressions():
try:
output_field = expr.output_field
if isinstance(output_field, bad_fields):
raise NotImplementedError(
'You cannot use Sum, Avg, StdDev, and Variance '
'aggregations on date/time fields in sqlite3 '
'since date/time is saved as text.'
)
except FieldError:
# Not every subexpression has an output_field which is fine
# to ignore.
pass
def check_expression_support(self, expression):
bad_fields = (fields.DateField, fields.DateTimeField, fields.TimeField)
bad_aggregates = (aggregates.Sum, aggregates.Avg, aggregates.Variance, aggregates.StdDev)
if isinstance(expression, bad_aggregates):
for expr in expression.get_source_expressions():
try:
output_field = expr.output_field
if isinstance(output_field, bad_fields):
raise NotImplementedError(
'You cannot use Sum, Avg, StdDev, and Variance '
'aggregations on date/time fields in sqlite3 '
'since date/time is saved as text.'
)
except FieldError:
# Not every subexpression has an output_field which is fine
# to ignore.
pass
def check_expression_support(self, expression):
bad_fields = (fields.DateField, fields.DateTimeField, fields.TimeField)
bad_aggregates = (aggregates.Sum, aggregates.Avg, aggregates.Variance, aggregates.StdDev)
if isinstance(expression, bad_aggregates):
for expr in expression.get_source_expressions():
try:
output_field = expr.output_field
if isinstance(output_field, bad_fields):
raise NotImplementedError(
'You cannot use Sum, Avg, StdDev, and Variance '
'aggregations on date/time fields in sqlite3 '
'since date/time is saved as text.'
)
except FieldError:
# Not every subexpression has an output_field which is fine
# to ignore.
pass
def check_expression_support(self, expression):
bad_fields = (fields.DateField, fields.DateTimeField, fields.TimeField)
bad_aggregates = (aggregates.Sum, aggregates.Avg, aggregates.Variance, aggregates.StdDev)
if isinstance(expression, bad_aggregates):
try:
output_field = expression.input_field.output_field
if isinstance(output_field, bad_fields):
raise NotImplementedError(
'You cannot use Sum, Avg, StdDev and Variance aggregations '
'on date/time fields in sqlite3 '
'since date/time is saved as text.')
except FieldError:
# not every sub-expression has an output_field which is fine to
# ignore
pass
def check_expression_support(self, expression):
bad_fields = (fields.DateField, fields.DateTimeField, fields.TimeField)
bad_aggregates = (aggregates.Sum, aggregates.Avg, aggregates.Variance, aggregates.StdDev)
if isinstance(expression, bad_aggregates):
try:
output_field = expression.input_field.output_field
if isinstance(output_field, bad_fields):
raise NotImplementedError(
'You cannot use Sum, Avg, StdDev and Variance aggregations '
'on date/time fields in sqlite3 '
'since date/time is saved as text.')
except FieldError:
# not every sub-expression has an output_field which is fine to
# ignore
pass
def check_expression_support(self, expression):
bad_fields = (fields.DateField, fields.DateTimeField, fields.TimeField)
bad_aggregates = (aggregates.Sum, aggregates.Avg, aggregates.Variance, aggregates.StdDev)
if isinstance(expression, bad_aggregates):
try:
output_field = expression.input_field.output_field
if isinstance(output_field, bad_fields):
raise NotImplementedError(
'You cannot use Sum, Avg, StdDev and Variance aggregations '
'on date/time fields in sqlite3 '
'since date/time is saved as text.')
except FieldError:
# not every sub-expression has an output_field which is fine to
# ignore
pass
