Django中日期时间型字段进行年月日时分秒分组统计

1.数据结构说明：

数据结构如下：modification字段为修改数据时间字段，格式为 年，月，日，时，分，秒。
案例场景为，根据modification字段，统计每个统计粒子，产生数据的条数。如需要统计2020年10月29日 每个小时段产生数据的条数。

要进行这种统计需要用到 Django的connection库。
统计年月日粒子用 date_trunc_sql，统计时分秒用 datetime_extract_sql

2.进行年月日粒子的统计

 2.1 官方 date_trunc_sql 原型

def datetime_trunc_sql(self, lookup_type, field_name, tzname):
"""
Given a lookup_type of 'year', 'month', 'day', 'hour', 'minute', or
'second', return the SQL that truncates the given datetime field
field_name to a datetime object with only the given specificity.
"""
raise NotImplementedError('subclasses of BaseDatabaseOperations may require a datetime_trunc_sql() method')

解释说明下：

函数需要传入三个参数：

• lookup_type：统计粒子（year->年，月->month，day->日，hour->时,minute->分,second->秒）

• field_name:统计字段的名次

• tzname：时区，在中国一般用的是东8区，传入8即可

2.2 年

from django.db import connection
from django.db.models import Count
# 'year', 'month', 'day', 'hour', 'minute', 'second'

select = {'year': connection.ops.datetime_trunc_sql('year', 'establish', 8)}
result = models.FocusOnRecord.objects.extra(select=select).values('year').annotate(number=Count('id')).order_by("year")[0:9]

for key in result:
print(key)

>>{'year': datetime.datetime(2019, 1, 1, 0, 0), 'number': 2168}
>>{'year': datetime.datetime(2020, 1, 1, 0, 0), 'number': 9369}

2.3 月

from django.db import connection
from django.db.models import Count
# 'year', 'month', 'day', 'hour', 'minute', 'second'

select = {'month': connection.ops.datetime_trunc_sql('month', 'establish', 8)}
result = models.FocusOnRecord.objects.extra(select=select).values('month').annotate(number=Count('id')).order_by("month")[0:9]

for key in result:
print(key)

>>{'month': datetime.datetime(2019, 6, 1, 0, 0), 'number': 8}
>>{'month': datetime.datetime(2019, 7, 1, 0, 0), 'number': 51}
>>{'month': datetime.datetime(2019, 8, 1, 0, 0), 'number': 118}
>>{'month': datetime.datetime(2019, 9, 1, 0, 0), 'number': 7}
>>{'month': datetime.datetime(2019, 10, 1, 0, 0), 'number': 731}
>>{'month': datetime.datetime(2019, 11, 1, 0, 0), 'number': 514}
>>{'month': datetime.datetime(2019, 12, 1, 0, 0), 'number': 739}
>>{'month': datetime.datetime(2020, 1, 1, 0, 0), 'number': 483}
>>{'month': datetime.datetime(2020, 2, 1, 0, 0), 'number': 921}

2.4 日

from django.db import connection
from django.db.models import Count
# 'year', 'month', 'day', 'hour', 'minute', 'second'

select = {'day': connection.ops.datetime_trunc_sql('day', 'establish', 8)}
result = models.FocusOnRecord.objects.extra(select=select).values('day').annotate(number=Count('id')).order_by("day")[0:9]

for key in result:
print(key)

>>{'day': datetime.datetime(2019, 6, 28, 0, 0), 'number': 1}
>>{'day': datetime.datetime(2019, 6, 29, 0, 0), 'number': 7}
>>{'day': datetime.datetime(2019, 7, 2, 0, 0), 'number': 1}
>>{'day': datetime.datetime(2019, 7, 11, 0, 0), 'number': 3}
>>{'day': datetime.datetime(2019, 7, 20, 0, 0), 'number': 32}
>>{'day': datetime.datetime(2019, 7, 21, 0, 0), 'number': 2}
>>{'day': datetime.datetime(2019, 7, 29, 0, 0), 'number': 3}
>>{'day': datetime.datetime(2019, 7, 31, 0, 0), 'number': 10}
>>{'day': datetime.datetime(2019, 8, 1, 0, 0), 'number': 20}

2.5 时

from django.db import connection
from django.db.models import Count
# 'year', 'month', 'day', 'hour', 'minute', 'second'

select = {'hour': connection.ops.datetime_trunc_sql('hour', 'establish', 8)}
result = models.FocusOnRecord.objects.extra(select=select).values('hour').annotate(number=Count('id')).order_by("hour")[0:9]

for key in result:
print(key)

>>{'hour': datetime.datetime(2019, 6, 28, 17, 0), 'number': 1}
>>{'hour': datetime.datetime(2019, 6, 29, 9, 0), 'number': 6}
>>{'hour': datetime.datetime(2019, 6, 29, 10, 0), 'number': 1}
>>{'hour': datetime.datetime(2019, 7, 2, 14, 0), 'number': 1}
>>{'hour': datetime.datetime(2019, 7, 11, 14, 0), 'number': 2}
>>{'hour': datetime.datetime(2019, 7, 11, 15, 0), 'number': 1}
>>{'hour': datetime.datetime(2019, 7, 20, 11, 0), 'number': 24}
>>{'hour': datetime.datetime(2019, 7, 20, 12, 0), 'number': 3}
>>{'hour': datetime.datetime(2019, 7, 20, 13, 0), 'number': 2}

2.6 分

from django.db import connection
from django.db.models import Count
# 'year', 'month', 'day', 'hour', 'minute', 'second'

select = {'minute': connection.ops.datetime_trunc_sql('minute', 'establish', 8)}
result = models.FocusOnRecord.objects.extra(select=select).values('minute').annotate(number=Count('id')).order_by("minute")[0:9]

for key in result:
print(key)

>>{'minute': datetime.datetime(2019, 6, 28, 17, 22), 'number': 1}
>>{'minute': datetime.datetime(2019, 6, 29, 9, 6), 'number': 4}
>>{'minute': datetime.datetime(2019, 6, 29, 9, 39), 'number': 1}
>>{'minute': datetime.datetime(2019, 6, 29, 9, 41), 'number': 1}
>>{'minute': datetime.datetime(2019, 6, 29, 10, 4), 'number': 1}
>>{'minute': datetime.datetime(2019, 7, 2, 14, 57), 'number': 1}
>>{'minute': datetime.datetime(2019, 7, 11, 14, 48), 'number': 1}
>>{'minute': datetime.datetime(2019, 7, 11, 14, 54), 'number': 1}
>>{'minute': datetime.datetime(2019, 7, 11, 15, 40), 'number': 1}

2.7 秒

from django.db import connection
from django.db.models import Count
# 'year', 'month', 'day', 'hour', 'minute', 'second'

select = {'second': connection.ops.datetime_trunc_sql('second', 'establish', 8)}
result = models.FocusOnRecord.objects.extra(select=select).values('second').annotate(number=Count('id')).order_by("second")[0:9]

for key in result:
print(key)

>>{'second': datetime.datetime(2019, 6, 28, 17, 22, 54), 'number': 1}
>>{'second': datetime.datetime(2019, 6, 29, 9, 6, 1), 'number': 1}
>>{'second': datetime.datetime(2019, 6, 29, 9, 6, 18), 'number': 1}
>>{'second': datetime.datetime(2019, 6, 29, 9, 6, 35), 'number': 1}
>>{'second': datetime.datetime(2019, 6, 29, 9, 6, 36), 'number': 1}
>>{'second': datetime.datetime(2019, 6, 29, 9, 39, 30), 'number': 1}
>>{'second': datetime.datetime(2019, 6, 29, 9, 41, 17), 'number': 1}
>>{'second': datetime.datetime(2019, 6, 29, 10, 4, 15), 'number': 1}
>>{'second': datetime.datetime(2019, 7, 2, 14, 57, 56), 'number': 1}

来源：https://blog.csdn.net/qq_22409661/article/details/109364457