pymongo的聚合操作
數據類型樣式
/* 1 */
{
"_id" : ObjectId("5e5a32fe2a89d7c2fc05b9fc"),
"user_id" : "1",
"amount" : 500,
"status" : "A"
}
/* 2 */
{
"_id" : ObjectId("5e5a33092a89d7c2fc05ba07"),
"user_id" : "1",
"amount" : 250,
"status" : "A"
}
/* 3 */
{
"_id" : ObjectId("5e5a33152a89d7c2fc05ba13"),
"user_id" : "2",
"amount" : 200,
"status" : "A"
}
/* 4 */
{
"_id" : ObjectId("5e5a33262a89d7c2fc05ba1c"),
"user_id" : "1",
"amount" : 300,
"status" : "B"
}
$match:過濾數據,返回符合條件的數據
def aggregate(self):
match_dict = {"$match":{"status":"A"}}
result = self.db["test_info"].aggregate([match_dict])
print(type(result))
print(result)
for i in result:
print(i)
<class 'pymongo.command_cursor.CommandCursor'>
<pymongo.command_cursor.CommandCursor object at 0x0000000002FF1648>
{'_id': ObjectId('5e5a32fe2a89d7c2fc05b9fc'), 'user_id': '1', 'amount': 500, 'status': 'A'}
{'_id': ObjectId('5e5a33092a89d7c2fc05ba07'), 'user_id': '1', 'amount': 250, 'status': 'A'}
{'_id': ObjectId('5e5a33152a89d7c2fc05ba13'), 'user_id': '2', 'amount': 200, 'status': 'A'}
$group:將過濾后的數據進行分組
def aggregate_match_group(self):
match_dict = {"$match": {"status": "A"}}
group_dict = {"$group":{"_id":"$user_id"}}
result = self.db["test_info"].aggregate([match_dict,group_dict])
print(type(result))
print(result)
for i in result:
print(i)
<class 'pymongo.command_cursor.CommandCursor'>
<pymongo.command_cursor.CommandCursor object at 0x0000000002FEF708>
{'_id': '2'}
{'_id': '1'}
# 注意: {"$group":{"_id":"$user_id"}} 分組的名稱必須是_id才行換成其他key或者自己重新命名key報錯:pymongo.errors.OperationFailure: The field 'user_id' must be an accumulator object
分組后,我們要求,每組的amount的總和是多少?
def aggregate_match_group(self):
match_dict = {"$match": {"status": "A"}}
group_dict = {"$group":{"_id":"$user_id","amount_total":{"$sum":"$amount"}}}
result = self.db["test_info"].aggregate([match_dict,group_dict])
print(type(result))
print(result)
for i in result:
print(i)
<class 'pymongo.command_cursor.CommandCursor'>
<pymongo.command_cursor.CommandCursor object at 0x0000000002FECD48>
{'_id': '2', 'amount_total': 200}
{'_id': '1', 'amount_total': 750}
# 注意:雖然分了兩組,但是其實第二組,包含了兩個內容
怎么才能顯示,每個里面成員的數量呢?
def aggregate_match_group(self):
match_dict = {"$match": {"status": "A"}}
group_dict = {"$group":{"_id":"$user_id","part_quantity":{"$sum":1}}}
result = self.db["test_info"].aggregate([match_dict,group_dict])
print(type(result))
print(result)
for i in result:
print(i)
<class 'pymongo.command_cursor.CommandCursor'>
<pymongo.command_cursor.CommandCursor object at 0x0000000002FF0E08>
{'_id': '2', 'part_quantity': 1}
{'_id': '1', 'part_quantity': 2}
# 注意: {"$sum":1} 表示組內有一個,按照1遞增, {"$sum":2} 就變成了 {'_id': '1', 'part_quantity': 4} 也就是按照2遞增!
如果我們想知道整個文檔里面符合$match過濾條件的文檔有多少個呢?
def aggregate_match_group(self):
match_dict = {"$match": {"status": "A"}}
group_dict = {"$group":{"_id":None,"part_quantity":{"$sum":1}}}
result = self.db["test_info"].aggregate([match_dict,group_dict])
print(type(result))
print(result)
for i in result:
print(i)
<class 'pymongo.command_cursor.CommandCursor'>
<pymongo.command_cursor.CommandCursor object at 0x0000000002FEBFC8>
{'_id': None, 'part_quantity': 3}
如果想知道整個collection里面有多少個文檔呢?
def aggregate_match_group(self):
match_dict = {"$match": {}}
group_dict = {"$group":{"_id":None,"part_quantity":{"$sum":1}}}
result = self.db["test_info"].aggregate([match_dict,group_dict])
print(type(result))
print(result)
for i in result:
print(i)
<class 'pymongo.command_cursor.CommandCursor'>
<pymongo.command_cursor.CommandCursor object at 0x0000000002FF1D48>
{'_id': None, 'part_quantity': 4}
將match過濾條件設置為,就可以作用於整個collection,match過濾條件設置為,就可以作用於整個collection,group分組條件"_id":None,表示文檔不分組,也就是整個文檔是一組!
/* 1 */
{
"_id" : ObjectId("5e5a41b22a89d7c2fc05c1c5"),
"user_id" : "1",
"name" : "科比",
"hometown" : "費城",
"age" : "100",
"gender" : "男"
}
/* 2 */
{
"_id" : ObjectId("5e5a41db2a89d7c2fc05c1dc"),
"user_id" : "2",
"name" : "納什",
"hometown" : "加拿大",
"age" : "100",
"gender" : "男"
}
/* 3 */
{
"_id" : ObjectId("5e5a42022a89d7c2fc05c1f1"),
"user_id" : "3",
"name" : "蔡徐坤",
"hometown" : "不詳",
"age" : "100",
"gender" : "女"
}
/* 4 */
{
"_id" : ObjectId("5e5a42252a89d7c2fc05c204"),
"user_id" : "4",
"name" : "gigi",
"hometown" : "洛杉磯",
"age" : "100",
"gender" : "女"
}
怎么獲取不同性別的人的所有user_id呢?
def aggregate_match_group(self):
match_dict = {"$match": {}}
group_dict = {"$group":{"_id":"$gender","user_id":{"$push":"$user_id"}}}
result = self.db["test_info"].aggregate([match_dict,group_dict])
print(type(result))
print(result)
for i in result:
print(i)
{'_id': '女', 'user_id': ['3', '4']}
{'_id': '男', 'user_id': ['1', '2']}
# 注意:$push:將結果追加到列表中
def aggregate_match_group(self):
match_dict = {"$match": {}}
group_dict = {"$group":{"_id":"$gender","user_id":{"$push":"$$ROOT"}}}
result = self.db["test_info"].aggregate([match_dict,group_dict])
print(type(result))
print(result)
for i in result:
print(i)
<class 'pymongo.command_cursor.CommandCursor'>
<pymongo.command_cursor.CommandCursor object at 0x0000000002FF0DC8>
{'_id': '女', 'user_id': [{'_id': ObjectId('5e5a42022a89d7c2fc05c1f1'), 'user_id': '3', 'name': '蔡徐坤', 'hometown': '不詳', 'age': '100', 'gender': '女'}, {'_id': ObjectId('5e5a42252a89d7c2fc05c204'), 'user_id': '4', 'name': 'gigi', 'hometown': '洛杉磯', 'age': '100', 'gender': '女'}]}
{'_id': '男', 'user_id': [{'_id': ObjectId('5e5a41b22a89d7c2fc05c1c5'), 'user_id': '1', 'name': '科比', 'hometown': '費城', 'age': '100', 'gender': '男'}, {'_id': ObjectId('5e5a41db2a89d7c2fc05c1dc'), 'user_id': '2', 'name': '納什', 'hometown': '加拿大', 'age': '100', 'gender': '男'}]}
# $$sort將整個文檔放入列表中
$gorup分組條件的 "_id" 多條件分組
def aggregate_match_group(self):
match_dict = {"$match": {}}
group_dict = {"$group":{"_id":{"user_id":"$user_id","name":"$name","hometown":"$hometown","age":"$age","gender":"$gender"}}}
result = self.db["test_info"].aggregate([match_dict,group_dict])
print(type(result))
print(result)
for i in result:
print(i)
{'_id': {'user_id': '4', 'name': 'gigi', 'hometown': '洛杉磯', 'age': '100', 'gender': '女'}}
{'_id': {'user_id': '3', 'name': '蔡徐坤', 'hometown': '不詳', 'age': '100', 'gender': '女'}}
{'_id': {'user_id': '2', 'name': '納什', 'hometown': '加拿大', 'age': '100', 'gender': '男'}}
{'_id': {'user_id': '1', 'name': '科比', 'hometown': '費城', 'age': '100', 'gender': '男'}}
def aggregate_match_group(self):
match_dict = {"$match": {}}
group_dict = {"$group":{"_id":{"name":"$name","age":"$age","gender":"$gender"}}}
result = self.db["test_info"].aggregate([match_dict,group_dict])
print(type(result))
print(result)
for i in result:
print(i)
<class 'pymongo.command_cursor.CommandCursor'>
<pymongo.command_cursor.CommandCursor object at 0x0000000002D4EE48>
{'_id': {'name': 'gigi', 'age': '100', 'gender': '女'}}
{'_id': {'name': '蔡徐坤', 'age': '100', 'gender': '女'}}
{'_id': {'name': '納什', 'age': '100', 'gender': '男'}}
{'_id': {'name': '科比', 'age': '100', 'gender': '男'}}
多條件分組,並統計數量
def aggregate_match_group(self):
match_dict = {"$match": {}}
group_dict = {"$group":{"_id":{"年齡":"$age","性別":"$gender"},"人數":{"$sum":1}}}
result = self.db["test_info"].aggregate([match_dict,group_dict])
print(type(result))
print(result)
for i in result:
print(i)
<class 'pymongo.command_cursor.CommandCursor'>
<pymongo.command_cursor.CommandCursor object at 0x0000000002FECD88>
{'_id': {'年齡': '100', '性別': '女'}, '人數': 2}
{'_id': {'年齡': '100', '性別': '男'}, '人數': 2}
對查詢數據進行修改
/* 1 */
{
"_id" : ObjectId("5e5a41b22a89d7c2fc05c1c5"),
"user_id" : "1",
"name" : "科比",
"hometown" : "費城",
"age" : "42",
"gender" : "男"
}
/* 2 */
{
"_id" : ObjectId("5e5a41db2a89d7c2fc05c1dc"),
"user_id" : "2",
"name" : "納什",
"hometown" : "加拿大",
"age" : "40",
"gender" : "男"
}
/* 3 */
{
"_id" : ObjectId("5e5a42022a89d7c2fc05c1f1"),
"user_id" : "3",
"name" : "蔡徐坤",
"hometown" : "不詳",
"age" : "3",
"gender" : "女"
}
/* 4 */
{
"_id" : ObjectId("5e5a42252a89d7c2fc05c204"),
"user_id" : "4",
"name" : "gigi",
"hometown" : "洛杉磯",
"age" : "14",
"gender" : "女"
}
獲取年齡年齡大於3歲的信息
$match
def aggregate_match_group(self):
match_dict = {"$match":{"age":{"$gt":"3"}}}
result = self.db["test_info"].aggregate([match_dict])
print(type(result))
print(result)
for i in result:
print(i)
<class 'pymongo.command_cursor.CommandCursor'>
<pymongo.command_cursor.CommandCursor object at 0x0000000002FF1C48>
{'_id': ObjectId('5e5a41b22a89d7c2fc05c1c5'), 'user_id': '1', 'name': '科比', 'hometown': '費城', 'age': '42', 'gender': '男'}
{'_id': ObjectId('5e5a41db2a89d7c2fc05c1dc'), 'user_id': '2', 'name': '納什', 'hometown': '加拿大', 'age': '40', 'gender': '男'}
# 查詢錯誤:gigi的年齡也是大於3,不顯示,我們將數據里面的年齡類型從str換成int類型,繼續查看
def aggregate_match_group(self):
match_dict = {"$match":{"age":{"$gt":3}}}
result = self.db["test_info"].aggregate([match_dict])
print(type(result))
print(result)
for i in result:
print(i)
<class 'pymongo.command_cursor.CommandCursor'>
<pymongo.command_cursor.CommandCursor object at 0x0000000002FF1C88>
{'_id': ObjectId('5e5a41b22a89d7c2fc05c1c5'), 'user_id': '1', 'name': '科比', 'hometown': '費城', 'age': 42, 'gender': '男'}
{'_id': ObjectId('5e5a41db2a89d7c2fc05c1dc'), 'user_id': '2', 'name': '納什', 'hometown': '加拿大', 'age': 40, 'gender': '男'}
{'_id': ObjectId('5e5a42252a89d7c2fc05c204'), 'user_id': '4', 'name': 'gigi', 'hometown': '洛杉磯', 'age': 14, 'gender': '女'}
# 查詢正確:因此當進行比較值的操作,注意字段類型必須是int類型
獲取年齡大於3歲,不同性別的人數
def aggregate_match_group(self):
match_dict = {"$match":{"age":{"$gt":3}}}
group_dict = {"$group":{"_id":"$gender","數量":{"$sum":1}}}
result = self.db["test_info"].aggregate([match_dict,group_dict])
print(type(result))
print(result)
for i in result:
print(i)
<class 'pymongo.command_cursor.CommandCursor'>
<pymongo.command_cursor.CommandCursor object at 0x0000000002FF1C88>
{'_id': '女', '數量': 1}
{'_id': '男', '數量': 2}
$preject類型與find里面的limit,需要顯示的設置為1,不顯示的設置為0
def aggregate_project(self):
project_dict = {"$project":{"_id":0,"name":1,"hometown":1}}
result = self.db["test_info"].aggregate([project_dict])
print(type(result))
print(result)
for i in result:
print(i)
<class 'pymongo.command_cursor.CommandCursor'>
<pymongo.command_cursor.CommandCursor object at 0x0000000002FE9F88>
{'name': '科比', 'hometown': '費城'}
{'name': '納什', 'hometown': '加拿大'}
{'name': '蔡徐坤', 'hometown': '不詳'}
{'name': 'gigi', 'hometown': '洛杉磯'}
# 注意:其他字段沒有賦值1就不顯示,但是_id字段除外,不設置,默認顯示
def aggregate_project(self):
group_dict = {"$group":{"_id":"$gender","quantity":{"$sum":1}}}
project_dict = {"$project":{"_id":1,"quantity":1}}
result = self.db["test_info"].aggregate([group_dict,project_dict])
print(type(result))
print(result)
for i in result:
print(i)
{'_id': '女', 'quantity': 2}
{'_id': '男', 'quantity': 2}
$sort:排序命令
年齡從小到大返回排序好的數據
def aggregate_sort(self):
sort_dict = {"$sort":{"age":1}}
result = self.db["test_info"].aggregate([sort_dict])
print(type(result))
print(result)
for i in result:
print(i)
<class 'pymongo.command_cursor.CommandCursor'>
<pymongo.command_cursor.CommandCursor object at 0x0000000003012148>
{'_id': ObjectId('5e5a42022a89d7c2fc05c1f1'), 'user_id': '3', 'name': '蔡徐坤', 'hometown': '不詳', 'age': 3, 'gender': '女'}
{'_id': ObjectId('5e5a42252a89d7c2fc05c204'), 'user_id': '4', 'name': 'gigi', 'hometown': '洛杉磯', 'age': 14, 'gender': '女'}
{'_id': ObjectId('5e5a41db2a89d7c2fc05c1dc'), 'user_id': '2', 'name': '納什', 'hometown': '加拿大', 'age': 40, 'gender': '男'}
{'_id': ObjectId('5e5a41b22a89d7c2fc05c1c5'), 'user_id': '1', 'name': '科比', 'hometown': '費城', 'age': 42, 'gender': '男'}
年齡從大到小返回排序好的數據
def aggregate_sort(self):
sort_dict = {"$sort":{"age":-1}}
result = self.db["test_info"].aggregate([sort_dict])
print(type(result))
print(result)
for i in result:
print(i)
<class 'pymongo.command_cursor.CommandCursor'>
<pymongo.command_cursor.CommandCursor object at 0x0000000002FE5F88>
{'_id': ObjectId('5e5a41b22a89d7c2fc05c1c5'), 'user_id': '1', 'name': '科比', 'hometown': '費城', 'age': 42, 'gender': '男'}
{'_id': ObjectId('5e5a41db2a89d7c2fc05c1dc'), 'user_id': '2', 'name': '納什', 'hometown': '加拿大', 'age': 40, 'gender': '男'}
{'_id': ObjectId('5e5a42252a89d7c2fc05c204'), 'user_id': '4', 'name': 'gigi', 'hometown': '洛杉磯', 'age': 14, 'gender': '女'}
{'_id': ObjectId('5e5a42022a89d7c2fc05c1f1'), 'user_id': '3', 'name': '蔡徐坤', 'hometown': '不詳', 'age': 3, 'gender': '女'}
數據類型
/* 10 */
{
"_id" : ObjectId("5e58c4102a89d7c2fc051ba4"),
"vaccine_name" : "破傷風",
"vaccine_id" : "2",
"user_id" : "110",
"farm_id" : "110",
"fold_id" : "110",
"farm_name" : "110牧場",
"fold_name" : "110圈舍",
"animal_number" : "133",
"equipment_number" : "133",
"type" : "goat",
"inject_quantity" : "100",
"vaccine_time" : ISODate("2020-06-15T15:45:22.000Z"),
"is_delete" : "0"
}
/* 11 */
{
"_id" : ObjectId("5e5a510d2a89d7c2fc05cac7"),
"vaccine_name" : "破傷風",
"vaccine_id" : "2",
"user_id" : "110",
"farm_id" : "110",
"fold_id" : "110",
"farm_name" : "110牧場",
"fold_name" : "110圈舍",
"animal_number" : "133",
"equipment_number" : "133",
"type" : "goat",
"inject_quantity" : "100",
"vaccine_time" : ISODate("2020-07-15T15:45:22.000Z"),
"is_delete" : "0"
}
/* 12 */
{
"_id" : ObjectId("5e5a511b2a89d7c2fc05cad2"),
"vaccine_name" : "破傷風",
"vaccine_id" : "2",
"user_id" : "110",
"farm_id" : "110",
"fold_id" : "110",
"farm_name" : "110牧場",
"fold_name" : "110圈舍",
"animal_number" : "133",
"equipment_number" : "133",
"type" : "goat",
"inject_quantity" : "100",
"vaccine_time" : ISODate("2020-08-15T15:45:22.000Z"),
"is_delete" : "0"
}
/* 13 */
{
"_id" : ObjectId("5e5a51282a89d7c2fc05cada"),
"vaccine_name" : "破傷風",
"vaccine_id" : "2",
"user_id" : "110",
"farm_id" : "110",
"fold_id" : "110",
"farm_name" : "110牧場",
"fold_name" : "110圈舍",
"animal_number" : "133",
"equipment_number" : "133",
"type" : "goat",
"inject_quantity" : "100",
"vaccine_time" : ISODate("2020-10-15T15:45:22.000Z"),
"is_delete" : "0"
}
/* 14 */
{
"_id" : ObjectId("5e5a51422a89d7c2fc05caec"),
"vaccine_name" : "破傷風",
"vaccine_id" : "2",
"user_id" : "110",
"farm_id" : "110",
"fold_id" : "110",
"farm_name" : "110牧場",
"fold_name" : "110圈舍",
"animal_number" : "133",
"equipment_number" : "133",
"type" : "goat",
"inject_quantity" : "100",
"vaccine_time" : ISODate("2020-11-15T15:45:22.000Z"),
"is_delete" : "0"
}
/* 15 */
{
"_id" : ObjectId("5e5a514d2a89d7c2fc05caf5"),
"vaccine_name" : "破傷風",
"vaccine_id" : "2",
"user_id" : "110",
"farm_id" : "110",
"fold_id" : "110",
"farm_name" : "110牧場",
"fold_name" : "110圈舍",
"animal_number" : "133",
"equipment_number" : "133",
"type" : "goat",
"inject_quantity" : "100",
"vaccine_time" : ISODate("2020-12-15T15:45:22.000Z"),
"is_delete" : "0"
}
需求:獲取equipment_number=13,vaccine_time按照時間倒敘排列,返回數據
def get_all_by_time_object(self,collection):
"""按照時間類型排序 vaccine_time的類型是 ISODate("2020-12-15T15:45:22.000Z")類型"""
if self.connect_result:
match_dict = {"$match":{"equipment_number":"133","type":"goat"}}
sort_dict = {"$sort":{"vaccine_time":-1}}
result = self.db[collection].aggregate([match_dict,sort_dict])
for i in result:
print(i)
{'_id': ObjectId('5e5a514d2a89d7c2fc05caf5'), 'vaccine_name': '破傷風', 'vaccine_id': '2', 'user_id': '110', 'farm_id': '110', 'fold_id': '110', 'farm_name': '110牧場', 'fold_name': '110圈舍', 'animal_number': '133', 'equipment_number': '133', 'type': 'goat', 'inject_quantity': '100', 'vaccine_time': datetime.datetime(2020, 12, 15, 15, 45, 22), 'is_delete': '0'}
{'_id': ObjectId('5e5a51422a89d7c2fc05caec'), 'vaccine_name': '破傷風', 'vaccine_id': '2', 'user_id': '110', 'farm_id': '110', 'fold_id': '110', 'farm_name': '110牧場', 'fold_name': '110圈舍', 'animal_number': '133', 'equipment_number': '133', 'type': 'goat', 'inject_quantity': '100', 'vaccine_time': datetime.datetime(2020, 11, 15, 15, 45, 22), 'is_delete': '0'}
{'_id': ObjectId('5e5a51282a89d7c2fc05cada'), 'vaccine_name': '破傷風', 'vaccine_id': '2', 'user_id': '110', 'farm_id': '110', 'fold_id': '110', 'farm_name': '110牧場', 'fold_name': '110圈舍', 'animal_number': '133', 'equipment_number': '133', 'type': 'goat', 'inject_quantity': '100', 'vaccine_time': datetime.datetime(2020, 10, 15, 15, 45, 22), 'is_delete': '0'}
{'_id': ObjectId('5e5a511b2a89d7c2fc05cad2'), 'vaccine_name': '破傷風', 'vaccine_id': '2', 'user_id': '110', 'farm_id': '110', 'fold_id': '110', 'farm_name': '110牧場', 'fold_name': '110圈舍', 'animal_number': '133', 'equipment_number': '133', 'type': 'goat', 'inject_quantity': '100', 'vaccine_time': datetime.datetime(2020, 8, 15, 15, 45, 22), 'is_delete': '0'}
{'_id': ObjectId('5e5a510d2a89d7c2fc05cac7'), 'vaccine_name': '破傷風', 'vaccine_id': '2', 'user_id': '110', 'farm_id': '110', 'fold_id': '110', 'farm_name': '110牧場', 'fold_name': '110圈舍', 'animal_number': '133', 'equipment_number': '133', 'type': 'goat', 'inject_quantity': '100', 'vaccine_time': datetime.datetime(2020, 7, 15, 15, 45, 22), 'is_delete': '0'}
{'_id': ObjectId('5e58c4102a89d7c2fc051ba4'), 'vaccine_name': '破傷風', 'vaccine_id': '2', 'user_id': '110', 'farm_id': '110', 'fold_id': '110', 'farm_name': '110牧場', 'fold_name': '110圈舍', 'animal_number': '133', 'equipment_number': '133', 'type': 'goat', 'inject_quantity': '100', 'vaccine_time': datetime.datetime(2020, 6, 15, 15, 45, 22), 'is_delete': '0'}
過濾掉一些字段,選擇性顯示需要的字段
def get_all_by_time_object(self,collection):
"""按照時間類型排序 vaccine_time的類型是 ISODate("2020-12-15T15:45:22.000Z")類型"""
if self.connect_result:
match_dict = {"$match":{"equipment_number":"133","type":"goat"}}
sort_dict = {"$sort":{"vaccine_time":-1}}
project_dict = {"$project":{"_id":0,"animal_number":1,"inject_quantity":1,"vaccine_time":1,"vaccine_name":1}}
result = self.db[collection].aggregate([match_dict,sort_dict,project_dict])
for i in result:
print(i)
{'vaccine_name': '破傷風', 'animal_number': '133', 'inject_quantity': '100', 'vaccine_time': datetime.datetime(2020, 12, 15, 15, 45, 22)}
{'vaccine_name': '破傷風', 'animal_number': '133', 'inject_quantity': '100', 'vaccine_time': datetime.datetime(2020, 11, 15, 15, 45, 22)}
{'vaccine_name': '破傷風', 'animal_number': '133', 'inject_quantity': '100', 'vaccine_time': datetime.datetime(2020, 10, 15, 15, 45, 22)}
{'vaccine_name': '破傷風', 'animal_number': '133', 'inject_quantity': '100', 'vaccine_time': datetime.datetime(2020, 8, 15, 15, 45, 22)}
{'vaccine_name': '破傷風', 'animal_number': '133', 'inject_quantity': '100', 'vaccine_time': datetime.datetime(2020, 7, 15, 15, 45, 22)}
{'vaccine_name': '破傷風', 'animal_number': '133', 'inject_quantity': '100', 'vaccine_time': datetime.datetime(2020, 6, 15, 15, 45, 22)}
$limit :限制返回的條數
def get_all_by_limit(self,collection):
if self.connect_result:
match_dict = {"$match": {"equipment_number": "133", "type": "goat"}}
sort_dict = {"$sort": {"vaccine_time": -1}}
project_dict = {
"$project": {"_id": 0, "animal_number": 1, "inject_quantity": 1, "vaccine_time": 1, "vaccine_name": 1}}
limit_dict = {"$limit":2}
result = self.db[collection].aggregate([match_dict, sort_dict, project_dict,limit_dict])
for i in result:
print(i)
{'vaccine_name': '破傷風', 'animal_number': '133', 'inject_quantity': '100', 'vaccine_time': datetime.datetime(2020, 12, 15, 15, 45, 22)}
{'vaccine_name': '破傷風', 'animal_number': '133', 'inject_quantity': '100', 'vaccine_time': datetime.datetime(2020, 11, 15, 15, 45, 22)}
$skip:跳過指定數量,返回剩余數量的內容
def get_all_by_skip(self,collection):
if self.connect_result:
match_dict = {"$match": {"equipment_number": "133", "type": "goat"}}
sort_dict = {"$sort": {"vaccine_time": -1}}
project_dict = {
"$project": {"_id": 0, "animal_number": 1, "inject_quantity": 1, "vaccine_time": 1, "vaccine_name": 1}}
skip_dict = {"$skip":2}
result = self.db[collection].aggregate([match_dict, sort_dict, project_dict,skip_dict])
for i in result:
print(i)
{'vaccine_name': '破傷風', 'animal_number': '133', 'inject_quantity': '100', 'vaccine_time': datetime.datetime(2020, 10, 15, 15, 45, 22)}
{'vaccine_name': '破傷風', 'animal_number': '133', 'inject_quantity': '100', 'vaccine_time': datetime.datetime(2020, 8, 15, 15, 45, 22)}
{'vaccine_name': '破傷風', 'animal_number': '133', 'inject_quantity': '100', 'vaccine_time': datetime.datetime(2020, 7, 15, 15, 45, 22)}
{'vaccine_name': '破傷風', 'animal_number': '133', 'inject_quantity': '100', 'vaccine_time': datetime.datetime(2020, 6, 15, 15, 45, 22)}
$ match過濾條件的或查詢
數據結構如下
/* 1 */
{
"_id" : ObjectId("5e5a41b22a89d7c2fc05c1c5"),
"user_id" : "1",
"name" : "科比",
"hometown" : "費城",
"age" : 42,
"gender" : "男"
}
/* 2 */
{
"_id" : ObjectId("5e5a41db2a89d7c2fc05c1dc"),
"user_id" : "2",
"name" : "納什",
"hometown" : "加拿大",
"age" : 40,
"gender" : "男"
}
/* 3 */
{
"_id" : ObjectId("5e5a42022a89d7c2fc05c1f1"),
"user_id" : "3",
"name" : "蔡徐坤",
"hometown" : "不詳",
"age" : 3,
"gender" : "女"
}
/* 4 */
{
"_id" : ObjectId("5e5a42252a89d7c2fc05c204"),
"user_id" : "4",
"name" : "gigi",
"hometown" : "洛杉磯",
"age" : 14,
"gender" : "女"
}
查詢年齡大於小於14歲或者大於40歲的人的信息
def get_all_by_or_match(self,collection):
if self.connect_result:
match_dict = {"$match": {"$or":[{"age":{"$gt":40}},{"age":{"$lt":14}}]}}
result = self.db[collection].aggregate([match_dict])
for i in result:
print(i)
{'_id': ObjectId('5e5a41b22a89d7c2fc05c1c5'), 'user_id': '1', 'name': '科比', 'hometown': '費城', 'age': 42, 'gender': '男'}
{'_id': ObjectId('5e5a42022a89d7c2fc05c1f1'), 'user_id': '3', 'name': '蔡徐坤', 'hometown': '不詳', 'age': 3, 'gender': '女'}
$ match過濾條件的范圍查詢
gt和gt和lt判斷的范圍都是int類型,那么我們要查找hometown 在列表中 ["加拿大","洛杉磯 ","費城 "]的數據,應該怎么辦呢?
def get_all_by_in_match(self,collection):
if self.connect_result:
match_dict = {"$match": {"hometown":{"$in":["加拿大","洛杉磯","費城"]}}}
result = self.db[collection].aggregate([match_dict])
for i in result:
print(i)
{'_id': ObjectId('5e5a41b22a89d7c2fc05c1c5'), 'user_id': '1', 'name': '科比', 'hometown': '費城', 'age': 42, 'gender': '男'}
{'_id': ObjectId('5e5a41db2a89d7c2fc05c1dc'), 'user_id': '2', 'name': '納什', 'hometown': '加拿大', 'age': 40, 'gender': '男'}
{'_id': ObjectId('5e5a42252a89d7c2fc05c204'), 'user_id': '4', 'name': 'gigi', 'hometown': '洛杉磯', 'age': 14, 'gender': '女'}
查詢年齡在[14,4,3]內的人的信息
def get_all_by_in_match(self,collection):
if self.connect_result:
match_dict = {"$match":{"age":{"$in":[14,40,3]}}}
result = self.db[collection].aggregate([match_dict])
for i in result:
print(i)
{'_id': ObjectId('5e5a41db2a89d7c2fc05c1dc'), 'user_id': '2', 'name': '納什', 'hometown': '加拿大', 'age': 40, 'gender': '男'}
{'_id': ObjectId('5e5a42022a89d7c2fc05c1f1'), 'user_id': '3', 'name': '蔡徐坤', 'hometown': '不詳', 'age': 3, 'gender': '女'}
{'_id': ObjectId('5e5a42252a89d7c2fc05c204'), 'user_id': '4', 'name': 'gigi', 'hometown': '洛杉磯', 'age': 14, 'gender': '女'}
數據結構如下
/* 1 */
{
"_id" : ObjectId("5e5b99052a89d7c2fc0653a0"),
"farm_id" : "1",
"animal_number" : "1",
"milking_time" : ISODate("2020-02-01T15:45:22.000Z"),
"milking_quantity" : 100
}
/* 2 */
{
"_id" : ObjectId("5e5b993d2a89d7c2fc0653cf"),
"farm_id" : "1",
"animal_number" : "2",
"milking_time" : ISODate("2020-02-01T18:46:33.000Z"),
"milking_quantity" : 120
}
/* 3 */
{
"_id" : ObjectId("5e5b996f2a89d7c2fc0653eb"),
"farm_id" : "1",
"animal_number" : "1",
"milking_time" : ISODate("2020-02-02T08:45:22.000Z"),
"milking_quantity" : 150
}
/* 4 */
{
"_id" : ObjectId("5e5b9a042a89d7c2fc06543e"),
"farm_id" : "1",
"animal_number" : "2",
"milking_time" : ISODate("2020-02-02T09:33:22.000Z"),
"milking_quantity" : 90
}
/* 5 */
{
"_id" : ObjectId("5e5b9a2b2a89d7c2fc065455"),
"farm_id" : "1",
"animal_number" : "1",
"milking_time" : ISODate("2020-02-03T10:30:30.000Z"),
"milking_quantity" : 98
}
/* 6 */
{
"_id" : ObjectId("5e5b9a452a89d7c2fc065464"),
"farm_id" : "1",
"animal_number" : "2",
"milking_time" : ISODate("2020-02-03T11:45:22.000Z"),
"milking_quantity" : 110
}
需求:牧場1下的所有羊,每天的產奶量平均值是多少,每三天的產奶量平均值是多少?
def get_all_by_avg_milk(self,collection):
if self.connect_result:
s_time = datetime(2020,2,1,00,00,00)
e_time = datetime(2020,2,1,23,59,59)
match_dict = {"$match": {"farm_id":"1","milking_time":{"$gte":s_time,"$lte":e_time}}}
group_dict = {"$group":{"_id":None,"2020-2-1日產奶量平均值為":{"$avg":"$milking_quantity"}}}
result = self.db[collection].aggregate([match_dict,group_dict])
for i in result:
print(i)
{'_id': None, '2020-2-1日產奶量平均值為': 110.0}
def get_all_by_avg_milk(self,collection):
if self.connect_result:
s_time = datetime(2020,2,1,00,00,00)
e_time = datetime(2020,2,3,23,59,59)
match_dict = {"$match": {"farm_id":"1","milking_time":{"$gte":s_time,"$lte":e_time}}}
group_dict = {"$group":{"_id":None,"三天產奶量平均值為":{"$avg":"$milking_quantity"}}}
result = self.db[collection].aggregate([match_dict,group_dict])
for i in result:
print(i)
{'_id': None, '三天產奶量平均值為': 111.33333333333333}
(100 + 120 + 150 + 90 + 98 + 110 )/3 = 222.6666
mogno給的結果是 222.666/2 = 111.3333 分組后一共取出六條數據,除以6了,造成結果錯誤,怎么解決呢?
先求總產量,然后分布計算結果
def get_all_by_avg_milk(self,collection):
if self.connect_result:
s_time = datetime(2020,2,1,00,00,00)
e_time = datetime(2020,2,3,23,59,59)
match_dict = {"$match": {"farm_id":"1","milking_time":{"$gte":s_time,"$lte":e_time}}}
group_dict = {"$group":{"_id":None,"三天產奶量總和為":{"$sum":"$milking_quantity"}}}
result = self.db[collection].aggregate([match_dict,group_dict])
for i in result:
print(i)
print("三天產奶量的平均值是%s"%(str(i.get("三天產奶量總和為")/3)))
{'_id': None, '三天產奶量總和為': 668}
三天產奶量的平均值是222.66666666666666
需求:輸出2020-2-1號產奶量最低的羊的編號和最高的羊的編號
def get_all_by_avg_milk(self,collection):
if self.connect_result:
s_time = datetime(2020,2,1,00,00,00)
e_time = datetime(2020,2,1,23,59,59)
match_dict = {"$match": {"farm_id":"1","milking_time":{"$gte":s_time,"$lte":e_time}}}
group_dict = {"$group":{"_id":None,"max_quantity":{"$max":"$milking_quantity"}}}
result = self.db[collection].aggregate([match_dict,group_dict])
for i in result:
print(i)
{'_id': None, 'max_quantity': 120}
max_quantity查庫獲得animal_nubmer
$unwind:針對文檔里面的數組進行操作
數據類型
{
"_id" : ObjectId("5e5ccf222a89d7c2fc06e9d0"),
"user_id" : "A",
"data" : [
{
"city" : "beijing",
"income" : 100000
},
{
"city" : "shanghai",
"income" : 150000
},
{
"city" : "shanghai",
"income" : 150000
}
]
}
結果是:將列表中的每一個內容和外面的鍵重新組合形成一條數據
def find_list(self,collection):
unwind_dict = {"$unwind":"$data"}
result = self.db[collection].aggregate([unwind_dict])
print(result)
print(type(result))
for i in result:
print(i)
<pymongo.command_cursor.CommandCursor object at 0x0000000002D58488>
<class 'pymongo.command_cursor.CommandCursor'>
{'_id': ObjectId('5e5ccf222a89d7c2fc06e9d0'), 'user_id': 'A', 'data': {'city': 'beijing', 'income': 100000}}
{'_id': ObjectId('5e5ccf222a89d7c2fc06e9d0'), 'user_id': 'A', 'data': {'city': 'shanghai', 'income': 150000}}
{'_id': ObjectId('5e5ccf222a89d7c2fc06e9d0'), 'user_id': 'A', 'data': {'city': 'shanghai', 'income': 150000}}
需求,計算A在上海收入的總和是多少?
def find_list_for_sum(self,collection):
match_dict1 = {"$match":{"user_id":"A"}}
unwind_dict = {"$unwind":"$data"}
match_dict2 = {"$match":{"data.city":"shanghai"}}
group_dict = {"$group":{"_id":"$data.city","收入總和":{"$sum":"$data.income"}}}
result = self.db[collection].aggregate([match_dict1,unwind_dict,match_dict2,group_dict])
print(result)
print(type(result))
for i in result:
print(i)
<pymongo.command_cursor.CommandCursor object at 0x0000000002FE9FC8>
<class 'pymongo.command_cursor.CommandCursor'>
{'_id': 'shanghai', '收入總和': 300000}
# 補充一下,如果是列表,怎么給列表里面添加數據,怎么給從列表里面刪除數據呢? addToSet和addToSet和pull
需求:給上面的數據的data列表中添加一條數據 {"city":"shenzhen","income":30000}
def add_to_list(self,collection):
query_dict = dict()
query_dict["user_id"] = "A"
result = self.db[collection].update(query_dict,{"$addToSet":{"data":{"city":"shenzhen","income":30000}}})
if result.get("nModified") == 1:
print("添加成功")
{
"_id" : ObjectId("5e5ccf222a89d7c2fc06e9d0"),
"user_id" : "A",
"data" : [
{
"city" : "beijing",
"income" : 100000
},
{
"city" : "shanghai",
"income" : 150000
},
{
"city" : "shanghai",
"income" : 150000
},
{
"city" : "shenzhen",
"income" : 30000
}
]
}
# 問題:這種天界方式:不能向data列表里面添加相同的鍵值對,連續插入{"city":"shenzhen","income":20000},並不會成功!
# TODO 待續
2020-3-20
需求:多個牧場下,每一個羊的飲水總數小於2的,返回其equipment_number
數據樣式:
/* 1 */
{
"_id" : ObjectId("5e746c378fc1e7a977e6be06"),
"farm_id" : "123",
"farm_name" : "測試",
"fold_id" : "123",
"fold_name" : "測試",
"device_number" : "123",
"equipment_number" : "123",
"animal_number" : "123",
"drink_quantity" : 100,
"type" : "goat",
"drink_time" : ISODate("2020-03-20T15:09:43.454Z")
}
/* 2 */
{
"_id" : ObjectId("5e746c448fc1e7a977e6be07"),
"farm_id" : "123",
"farm_name" : "測試",
"fold_id" : "123",
"fold_name" : "測試",
"device_number" : "123",
"equipment_number" : "123",
"animal_number" : "123",
"drink_quantity" : 200,
"type" : "goat",
"drink_time" : ISODate("2020-03-20T15:09:56.139Z")
}
/* 3 */
{
"_id" : ObjectId("5e746c488fc1e7a977e6be08"),
"farm_id" : "123",
"farm_name" : "測試",
"fold_id" : "123",
"fold_name" : "測試",
"device_number" : "123",
"equipment_number" : "123",
"animal_number" : "123",
"drink_quantity" : 300,
"type" : "goat",
"drink_time" : ISODate("2020-03-20T15:10:00.115Z")
}
/* 4 */
{
"_id" : ObjectId("5e7474b1e47b4ffc8fbd4d3b"),
"farm_id" : "123",
"farm_name" : "測試",
"fold_id" : "123",
"fold_name" : "測試",
"device_number" : "123",
"equipment_number" : "124",
"animal_number" : "124",
"drink_quantity" : 100,
"type" : "goat",
"drink_time" : ISODate("2020-03-20T15:45:53.727Z")
}
/* 5 */
{
"_id" : ObjectId("5e7474b7e47b4ffc8fbd4d3c"),
"farm_id" : "123",
"farm_name" : "測試",
"fold_id" : "123",
"fold_name" : "測試",
"device_number" : "123",
"equipment_number" : "124",
"animal_number" : "124",
"drink_quantity" : 200,
"type" : "goat",
"drink_time" : ISODate("2020-03-20T15:45:59.674Z")
}
/* 6 */
{
"_id" : ObjectId("5e7474c0e47b4ffc8fbd4d3d"),
"farm_id" : "123",
"farm_name" : "測試",
"fold_id" : "123",
"fold_name" : "測試",
"device_number" : "123",
"equipment_number" : "125",
"animal_number" : "125",
"drink_quantity" : 100,
"type" : "goat",
"drink_time" : ISODate("2020-03-20T15:46:08.953Z")
}
/* 7 */
{
"_id" : ObjectId("5e748632217a21f9adb48c12"),
"farm_id" : "125",
"farm_name" : "測試",
"fold_id" : "125",
"fold_name" : "測試",
"device_number" : "125",
"equipment_number" : "125",
"animal_number" : "125",
"drink_quantity" : 100,
"type" : "goat",
"drink_time" : ISODate("2020-03-20T17:00:34.398Z")
}
查詢 123 125牧場下,飲水次數小於2的equipment_mumber,飲水次數就是有一條數據,就是飲水一次
def aggregate_many(self):
# 獲取所有牧場下,飲水次數小於2的羊的equipment_number
match_dict = {"$match":{"farm_id":{"$in":["123","125"]}}}
project_dict = {"$project":{"_id":0}}
group_dict = {"$group":{"_id":{"equipment_number":"$equipment_number","farm_id":"$farm_id"},"total_count":{"$sum":1}}}
# match_dict_1 = {"$match":{"total_count":{"$lt":2}}}
result = self.db["sheep_water_intake"].aggregate([match_dict,project_dict,group_dict])
for i in result:
print(i)
{'_id': {'equipment_number': '125', 'farm_id': '125'}, 'total_count': 1}
{'_id': {'equipment_number': '125', 'farm_id': '123'}, 'total_count': 1}
{'_id': {'equipment_number': '124', 'farm_id': '123'}, 'total_count': 2}
{'_id': {'equipment_number': '123', 'farm_id': '123'}, 'total_count': 3}
首先考慮去重的問題,group_dict = {"$group":{"_id":{"equipment_number":"equipmentnumber","farmid":"equipmentnumber","farmid":"farm_id"},"total_count":{"$sum":1}}}
group應該是先分組,分完組之后,進行累加,先看看不分組的數據
def aggregate_many(self):
# 獲取所有牧場下,飲水次數小於2的羊的equipment_number
match_dict = {"$match":{"farm_id":{"$in":["123","125"]}}}
project_dict = {"$project":{"_id":0}}
# group_dict = {"$group":{"_id":{"equipment_number":"$equipment_number","farm_id":"$farm_id"},"total_count":{"$sum":1}}}
match_dict_1 = {"$match":{"total_count":{"$lt":2}}}
result = self.db["sheep_water_intake"].aggregate([match_dict,project_dict])
for i in result:
print(i)
{'farm_id': '123', 'farm_name': '測試', 'fold_id': '123', 'fold_name': '測試', 'device_number': '123', 'equipment_number': '123', 'animal_number': '123', 'drink_quantity': 100, 'type': 'goat', 'drink_time': datetime.datetime(2020, 3, 20, 15, 9, 43, 454000)}
{'farm_id': '123', 'farm_name': '測試', 'fold_id': '123', 'fold_name': '測試', 'device_number': '123', 'equipment_number': '123', 'animal_number': '123', 'drink_quantity': 200, 'type': 'goat', 'drink_time': datetime.datetime(2020, 3, 20, 15, 9, 56, 139000)}
{'farm_id': '123', 'farm_name': '測試', 'fold_id': '123', 'fold_name': '測試', 'device_number': '123', 'equipment_number': '123', 'animal_number': '123', 'drink_quantity': 300, 'type': 'goat', 'drink_time': datetime.datetime(2020, 3, 20, 15, 10, 0, 115000)}
{'farm_id': '123', 'farm_name': '測試', 'fold_id': '123', 'fold_name': '測試', 'device_number': '123', 'equipment_number': '124', 'animal_number': '124', 'drink_quantity': 100, 'type': 'goat', 'drink_time': datetime.datetime(2020, 3, 20, 15, 45, 53, 727000)}
{'farm_id': '123', 'farm_name': '測試', 'fold_id': '123', 'fold_name': '測試', 'device_number': '123', 'equipment_number': '124', 'animal_number': '124', 'drink_quantity': 200, 'type': 'goat', 'drink_time': datetime.datetime(2020, 3, 20, 15, 45, 59, 674000)}
{'farm_id': '123', 'farm_name': '測試', 'fold_id': '123', 'fold_name': '測試', 'device_number': '123', 'equipment_number': '125', 'animal_number': '125', 'drink_quantity': 100, 'type': 'goat', 'drink_time': datetime.datetime(2020, 3, 20, 15, 46, 8, 953000)}
{'farm_id': '125', 'farm_name': '測試', 'fold_id': '125', 'fold_name': '測試', 'device_number': '125', 'equipment_number': '125', 'animal_number': '125', 'drink_quantity': 100, 'type': 'goat', 'drink_time': datetime.datetime(2020, 3, 20, 17, 0, 34, 398000)}
最終的結果
def aggregate_many(self):
# 獲取所有牧場下,飲水次數小於2的羊的equipment_number
match_dict = {"$match":{"farm_id":{"$in":["123","125"]}}}
project_dict = {"$project":{"_id":0}}
group_dict = {"$group":{"_id":{"equipment_number":"$equipment_number","farm_id":"$farm_id"},"total_count":{"$sum":1}}}
match_dict_1 = {"$match":{"total_count":{"$lt":2}}}
result = self.db["sheep_water_intake"].aggregate([match_dict,project_dict,group_dict,match_dict_1])
for i in result:
print(i)
{'_id': {'equipment_number': '125', 'farm_id': '125'}, 'total_count': 1}
{'_id': {'equipment_number': '125', 'farm_id': '123'}, 'total_count': 1}
$lookup 多表聯查
test2
{
"_id" : ObjectId("5e7c756b2a89d7c2fc178f57"),
"brand" : "惠普公司",
"address" : "美國"
}
test1
{
"_id" : ObjectId("5e7c753b2a89d7c2fc178f38"),
"name" : "暗夜精靈筆記本電腦",
"brand_id" : "5e7c756b2a89d7c2fc178f57",
}
{
"_id" : ObjectId("5e7c75d02a89d7c2fc178fb0"),
"name" : "暗夜精靈2",
"brand_id" : "5e7c756b2a89d7c2fc178f57",
"price" : 5600
}
通過test2的_id獲取所有brand_id為_id的電腦名稱和價格
from pymongo import MongoClient
class PyMongoTest(object):
def __init__(self):
self.host = "xx"
self.port = xx
self.username = "xx"
self.password = "xx"
self.database = "xx"
self.client = MongoClient(host=self.host,port=self.port)
self.db = self.client[self.database]
self.connect_result = False
if self.username and self.password:
self.connect_result = self.db.authenticate(self.username,self.password)
def aggregate_two_collection(self):
collection_one = "test2"
collection_two = "test1"
lookup_dict = {"$lookup":{"from":collection_two,"localField":"_id","foreignField":"brand_id","as":"brand_product"}}
result = self.db[collection_one].aggregate([lookup_dict])
for r in result:
print(r)
p = PyMongoTest()
p.aggregate_two_collection()
# 結果
{'_id': ObjectId('5e7c756b2a89d7c2fc178f57'), 'brand': '惠普公司', 'address': '美國', 'brand_product': []}
將test2改為
{
"_id" : ObjectId("5e7c756b2a89d7c2fc178f57"),
"brand" : "惠普公司",
"address" : "美國",
"oid" : "5e7c756b2a89d7c2fc178f57"
}
def aggregate_two_collection(self):
collection_one = "test2"
collection_two = "test1"
lookup_dict = {"$lookup":{"from":collection_two,"localField":"oid","foreignField":"brand_id","as":"brand_product"}}
result = self.db[collection_one].aggregate([lookup_dict])
for r in result:
print(r)
# 結果
{'_id': ObjectId('5e7c756b2a89d7c2fc178f57'), 'brand': '惠普公司', 'address': '美國', 'oid': '5e7c756b2a89d7c2fc178f57', 'brand_product': [{'_id': ObjectId('5e7c753b2a89d7c2fc178f38'), 'name': '暗夜精靈筆記本電腦', 'brand_id': '5e7c756b2a89d7c2fc178f57'}, {'_id': ObjectId('5e7c75d02a89d7c2fc178fb0'), 'name': '暗夜精靈2', 'brand_id': '5e7c756b2a89d7c2fc178f57', 'price': 5600}]}
可以看出:from是要關聯的集合名,localField是關聯的字段,foreignField也是關聯的字段,但是必須注意,這兩個字段的類型必須相同,要不就拿不出數據,as就是關聯后,列表的名稱
修改test1
/* 1 */
{
"_id" : ObjectId("5e7c753b2a89d7c2fc178f38"),
"name" : "暗夜精靈筆記本電腦",
"brand_id" : "5e7c756b2a89d7c2fc178f57F",
}
/* 2 */
{
"_id" : ObjectId("5e7c75d02a89d7c2fc178fb0"),
"name" : "暗夜精靈2",
"brand_id" : "5e7c756b2a89d7c2fc178f57D",
"price" : 5600
}
{'_id': ObjectId('5e7c756b2a89d7c2fc178f57'), 'brand': '惠普公司', 'address': '美國', 'oid': '5e7c756b2a89d7c2fc178f57', 'brand_product': []}
說明 localField是關聯的字段,foreignField也是關聯的字段,值也必須相同。
將test1兩個數據的brand_id修改成和test1的oid值一樣,做下面測試
關聯后,只想輸出部分字段,怎么辦?
def aggregate_two_collection(self):
collection_one = "test2"
collection_two = "test1"
lookup_dict = {"$lookup":{"from":collection_two,"localField":"oid","foreignField":"brand_id","as":"brand_product"}}
project_dict = {"$project":{"_id":0,"oid":0}}
result = self.db[collection_one].aggregate([lookup_dict,project_dict])
for r in result:
print(r)
# 結果
{'brand': '惠普公司', 'address': '美國', 'brand_product': [{'_id': ObjectId('5e7c753b2a89d7c2fc178f38'), 'name': '暗夜精靈筆記本電腦', 'brand_id': '5e7c756b2a89d7c2fc178f57'}, {'_id': ObjectId('5e7c75d02a89d7c2fc178fb0'), 'name': '暗夜精靈2', 'brand_id': '5e7c756b2a89d7c2fc178f57', 'price': 5600}]}
project只影響原表的字段輸出,不影響要關聯表的字段,如果需要影響要關聯表的字段輸出呢?
更改test1數據為
/* 1 */
{
"_id" : ObjectId("5e7c753b2a89d7c2fc178f38"),
"name" : "暗夜精靈筆記本電腦",
"brand_id" : "5e7c756b2a89d7c2fc178f57",
"price" : 5000
}
/* 2 */
{
"_id" : ObjectId("5e7c75d02a89d7c2fc178fb0"),
"name" : "暗夜精靈2",
"brand_id" : "5e7c756b2a89d7c2fc178f57",
"price" : 5600
}
def aggregate_two_collection(self):
collection_one = "test2"
collection_two = "test1"
lookup_dict = {"$lookup":{"from":collection_two,"localField":"oid","foreignField":"brand_id","as":"brand_product"}}
project_dict = {"$project":{"_id":0,"brand_product._id":0}}
result = self.db[collection_one].aggregate([lookup_dict,project_dict])
for r in result:
print(r)
#結果
{'brand': '惠普公司', 'address': '美國', 'oid': '5e7c756b2a89d7c2fc178f57', 'brand_product': [{'name': '暗夜精靈筆記本電腦', 'brand_id': '5e7c756b2a89d7c2fc178f57', 'price': 5000}, {'name': '暗夜精靈2', 'brand_id': '5e7c756b2a89d7c2fc178f57', 'price': 5600}]}
計算兩款電腦的平均值?
def aggregate_two_collection(self):
collection_one = "test2"
collection_two = "test1"
lookup_dict = {"$lookup":{"from":collection_two,"localField":"oid","foreignField":"brand_id","as":"brand_product"}}
project_dict = {"$project":{"_id":0,"brand_product._id":0}}
unwind_dict = {"$unwind":"$brand_product"}
group_dict = {"$group":{"_id":{"oid":"$oid"},"avg_price":{"$avg":"$brand_product.price"}}}
result = self.db[collection_one].aggregate([lookup_dict,project_dict,unwind_dict,group_dict])
for r in result:
print(r)
# 結果
{'_id': {'oid': '5e7c756b2a89d7c2fc178f57'}, 'avg_price': 5300.0}
$substr 切割字符串操作
/* 1 */
{
"_id" : ObjectId("5e7dc3322a89d7c2fc18605d"),
"animal_number" : "1001",
"status" : "0",
"time" : ISODate("2020-03-01T23:00:00.000Z")
}
/* 2 */
{
"_id" : ObjectId("5e7dc3462a89d7c2fc18606e"),
"animal_number" : "1001",
"status" : "1",
"time" : ISODate("2020-03-01T12:00:00.000Z")
}
/* 3 */
{
"_id" : ObjectId("5e7dc35d2a89d7c2fc186093"),
"animal_number" : "1001",
"status" : "0",
"time" : ISODate("2020-03-02T15:00:00.000Z")
}
/* 4 */
{
"_id" : ObjectId("5e7dc3702a89d7c2fc1860a4"),
"animal_number" : "1001",
"status" : "1",
"time" : ISODate("2020-03-02T22:33:00.000Z")
}
/* 5 */
{
"_id" : ObjectId("5e7dc3912a89d7c2fc1860c3"),
"animal_number" : "1001",
"status" : "0",
"time" : ISODate("2020-03-03T21:39:00.000Z")
}
/* 6 */
{
"_id" : ObjectId("5e7dc39e2a89d7c2fc1860ce"),
"animal_number" : "1001",
"status" : "1",
"time" : ISODate("2020-03-04T23:00:00.000Z")
}
獲取每天status為0的次數,和status為1的次數
def aggregate(self):
match_dict = {"$match":{"animal_number":"1001"}}
project = {"$project":{"_id":0,"animal_number":"$animal_number","status":"$status","time":{"$substr":["$time",0,10]}}}
result = self.db["test2"].aggregate([match_dict,project])
for info in result:
print(info)
# 結果
{'animal_number': '1001', 'status': '0', 'time': '2020-03-01'}
{'animal_number': '1001', 'status': '1', 'time': '2020-03-01'}
{'animal_number': '1001', 'status': '0', 'time': '2020-03-02'}
{'animal_number': '1001', 'status': '1', 'time': '2020-03-02'}
{'animal_number': '1001', 'status': '0', 'time': '2020-03-03'}
{'animal_number': '1001', 'status': '1', 'time': '2020-03-04'}
project里面使用 "status":1和"status":"$status"表示的含義一樣,均表示需要展示
$substr:["$需要切割字段的名字",起始位置,終止位置]
def aggregate(self):
match_dict = {"$match":{"animal_number":"1001"}}
project = {"$project":{"_id":0,"animal_number":"$animal_number","status":"$status","time":{"$substr":["$time",0,10]}}}
group_dict = {"$group":{"_id":{"time":"$time","status":"$status"},"every_status_every_day_count":{"$sum":1}}}
result = self.db["test2"].aggregate([match_dict,project,group_dict])
for info in result:
print(info)
# 結果
{'_id': {'time': '2020-03-03', 'status': '0'}, 'every_status_every_day_count': 1}
{'_id': {'time': '2020-03-04', 'status': '1'}, 'every_status_every_day_count': 1}
{'_id': {'time': '2020-03-01', 'status': '1'}, 'every_status_every_day_count': 1}
{'_id': {'time': '2020-03-01', 'status': '0'}, 'every_status_every_day_count': 1}
{'_id': {'time': '2020-03-02', 'status': '0'}, 'every_status_every_day_count': 1}
{'_id': {'time': '2020-03-02', 'status': '1'}, 'every_status_every_day_count': 1}

