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  • Committer: Package Import Robot
  • Author(s): Raphaël Hertzog
  • Date: 2014-09-17 14:15:11 UTC
  • mfrom: (1.3.17) (6.2.18 experimental)
  • Revision ID: package-import@ubuntu.com-20140917141511-icneokthe9ww5sk4
Tags: 1.7-2
* Release to unstable.
* Add a migrate-south sample script to help users apply their South
  migrations. Thanks to Brian May.

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django/db/models/sql/aggregates.py
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import copy
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from django.db.models.fields import IntegerField, FloatField
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# Fake fields used to identify aggregate types in data-conversion operations.
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ordinal_aggregate_field = IntegerField()
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computed_aggregate_field = FloatField()
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class Aggregate(object):
 
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from django.db.models.lookups import RegisterLookupMixin
 
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from django.utils.functional import cached_property
 
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__all__ = ['Aggregate', 'Avg', 'Count', 'Max', 'Min', 'StdDev', 'Sum', 'Variance']
 
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class Aggregate(RegisterLookupMixin):
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    """
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    Default SQL Aggregate.
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    """
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        while tmp and isinstance(tmp, Aggregate):
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            if getattr(tmp, 'is_ordinal', False):
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                tmp = ordinal_aggregate_field
 
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                tmp = self._ordinal_aggregate_field
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            elif getattr(tmp, 'is_computed', False):
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                tmp = computed_aggregate_field
 
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                tmp = self._computed_aggregate_field
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            else:
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                tmp = tmp.source
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        self.field = tmp
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    # Two fake fields used to identify aggregate types in data-conversion operations.
 
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    @cached_property
 
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    def _ordinal_aggregate_field(self):
 
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        return IntegerField()
 
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    @cached_property
 
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    def _computed_aggregate_field(self):
 
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        return FloatField()
 
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    def relabeled_clone(self, change_map):
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        clone = copy.copy(self)
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        if isinstance(self.col, (list, tuple)):
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        if hasattr(self.col, 'as_sql'):
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            field_name, params = self.col.as_sql(qn, connection)
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        elif isinstance(self.col, (list, tuple)):
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            field_name = '.'.join([qn(c) for c in self.col])
 
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            field_name = '.'.join(qn(c) for c in self.col)
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        else:
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            field_name = self.col
 
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            field_name = qn(self.col)
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        substitutions = {
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            'function': self.sql_function,
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        return self.sql_template % substitutions, params
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    def get_group_by_cols(self):
 
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        return []
 
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    @property
 
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    def output_field(self):
 
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        return self.field
 
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class Avg(Aggregate):
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    is_computed = True
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    sql_function = 'AVG'
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class Count(Aggregate):
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    is_ordinal = True
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    sql_function = 'COUNT'
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    def __init__(self, col, distinct=False, **extra):
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        super(Count, self).__init__(col, distinct='DISTINCT ' if distinct else '', **extra)
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class Max(Aggregate):
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    sql_function = 'MAX'
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class Min(Aggregate):
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    sql_function = 'MIN'
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class StdDev(Aggregate):
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    is_computed = True
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        super(StdDev, self).__init__(col, **extra)
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        self.sql_function = 'STDDEV_SAMP' if sample else 'STDDEV_POP'
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class Sum(Aggregate):
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    sql_function = 'SUM'
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class Variance(Aggregate):
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    is_computed = True
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