模型这块还差不少呢

orm_demo/orm_crud.py

@@ -1,4 +1,6 @@
 from orm_demo.models import *
+from django.db.models import F, Q, Count
+from django.db import connection
 
 # 插入数据
 # 先实例化对象，然后为对象赋值
@@ -126,11 +128,196 @@ for user in skill_py.user.all():
 user_del = UserExtendInfo.objects.get(id=5)
 skill_del = SkillInfo.objects.get(id=7)
 result = skill_del.user.remove(user_del)
+print(result)
 
 # 通过id指定删除哪个用户
 skill_del = SkillInfo.objects.get(id=1)
 result = skill_del.user.remove(2)
+print(result)
 
 # 清除全部
 skill_del = SkillInfo.objects.get(id=8)
 result = skill_del.user.clear()
+print(result)
+
+# ForeignKey 直接获取关联表数据, 只能用在一对多设置外键的情况
+card_data = CardInfo.objects.select_related('user')
+for card in card_data:
+    print(card.user)
+
+# ManyToMany 多对多直接获取关联表数据
+skill_data = SkillInfo.objects.prefetch_related('user')
+for skill in skill_data:
+    print(skill.skill_name)
+    users = skill.user.all()
+    for user in users:
+        print(user.true_name)
+
+# F()函数
+users = UserExtendInfo.objects.all()
+for user in users:
+    user.salary = F('salary') + 1000
+    user.save()
+for user in users:
+    user.refresh_from_db()
+    print(user.salary)
+
+# Q()函数 用于多条件查询
+user = UserExtendInfo.objects.filter(Q(age__gt=30) & Q(salary__gt=10000)).first()
+print(user.username)
+
+# 执行原生SQL
+users = UserExtendInfo.objects.raw("SELECT * FROM orm_user_base_info")
+for user in users:
+    print(type(user), user.username)
+
+sql = "SELECT * FROM orm_user_extend_info WHERE age > %s and salary > %s"
+users = UserExtendInfo.objects.raw(sql, [30, 10000])
+for user in users:
+    print(type(user), user.username)
+
+# connect 游标
+# 插入数据
+import django.utils.timezone as timezone
+
+time_now = timezone.now()
+cursor = connection.cursor()
+sql = "INSERT INTO orm_skill_info (skill_name, createDate) VALUES (%s, %s)"
+cursor.execute(sql, ('selenium', time_now))
+cursor.close()
+
+# 查询数据
+sql = "SELECT * FROM orm_user_extend_info"
+cursor = connection.cursor()
+cursor.execute(sql)
+row = cursor.fetchone()
+print(row)
+cursor.close()
+
+# 更新数据
+cursor = connection.cursor()
+try:
+    update_sql = "UPDATE orm_depart_info SET depart_name = %s WHERE id = %s"
+    data = ('开发部', 1)
+    cursor.execute(update_sql, data)
+    rowcount = cursor.rowcount
+    print(rowcount)
+    connection.commit()
+except Exception as e:
+    print(e)
+    connection.rollback()
+finally:
+    cursor.close()
+
+# 事务处理 transaction
+from django.db import transaction
+
+
+# 方式1：修饰器
+
+@transaction.atomic
+def trans(request):
+    save_id = transaction.savepoint()  # 开启事件
+    try:
+        # somecode
+        transaction.savepoint_commit(save_id)  # 提交事件
+    except Exception as e:
+        print(e)
+        transaction.savepoint_rollback(save_id)  # 回滚事件
+
+
+# 方式2： with语句
+
+def trans_with(request):
+    with transaction.atomic():
+        save_id = transaction.savepoint()  # 开启事件
+        try:
+            # some code
+            transaction.commit(save_id)  # 提交事件
+        except Exception as e:
+            print(e)
+            transaction.rollback(save_id)  # 回滚事件
+
+
+# 基本查询
+# get 当查询结果多余一条时报错
+user = BaseUserInfo.objects.get(id=2)
+print(user)
+
+# exclude 排除查询出来的数据
+users = UserExtendInfo.objects.exclude(age__lt=30)
+for user in users:
+    print(user.true_name)
+
+# filter 过滤数据
+users = UserExtendInfo.objects.filter(Q(age__gte=30) & Q(department__in=['开发部', '测试部']))
+for user in users:
+    print(user.true_name)
+
+# __gt __gte __lt __lte __in __contains  __year __month __day
+users = BaseUserInfo.objects.filter(username__contains="孙")
+for user in users:
+    print(user)
+
+users = BaseUserInfo.objects.filter(create_date__year='2023')
+for user in users:
+    print(user.create_date)
+
+users = BaseUserInfo.objects.filter(create_date__day='08')
+for user in users:
+    print(user.create_date)
+
+# values 用于指定显示具体字段
+users = UserExtendInfo.objects.filter(username='张三').values('username', 'true_name', 'salary')
+for user in users:
+    print(user)
+    print(user['true_name'])
+
+# distinct 去重
+departs = UserExtendInfo.objects.distinct().values('department')
+for d in departs:
+    print(d)
+
+# 链式过滤器
+users = UserExtendInfo.objects.filter(age__range=[20, 30]).exclude(salary__lt=17000)
+for user in users:
+    print(user.username)
+
+# 结果切片
+skills = SkillInfo.objects.all()[1:3]
+print(skills)
+
+# 排序 order_by
+user_salary = UserExtendInfo.objects.order_by('salary').all()
+for user in user_salary:
+    print(user.salary)
+
+# 排序 desc
+user_salary = UserExtendInfo.objects.order_by(F('salary').desc())
+for user in user_salary:
+    print(user.salary)
+
+# 排序 asc
+user_salary = UserExtendInfo.objects.order_by(F('salary').asc())
+for user in user_salary:
+    print(user.salary)
+
+# group_by query形式
+users = UserExtendInfo.objects.all()
+users.query.group_by = ['department']
+for user in users:
+    print(user.username, user.department)
+
+# group_by aggregated count
+users = UserExtendInfo.objects.values('username').aaggregate(count=Count('department'))
+print(users)
+
+# count
+
+
+# sum
+
+# UNION
+
+
+# JOIN