Add query example model definitions

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examples/query_library.py

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+# Collection of Query Examples.
+# https://docs.peewee-orm.com/en/latest/peewee/query_library.html
+
+from functools import partial
+from peewee import *
+
+
+db = PostgresqlDatabase('peewee_clubdata')
+
+class BaseModel(Model):
+    class Meta:
+        database = db
+
+class Member(BaseModel):
+    memid = AutoField()  # Auto-incrementing primary key.
+    surname = CharField()
+    firstname = CharField()
+    address = CharField(max_length=300)
+    zipcode = IntegerField()
+    telephone = CharField()
+    recommendedby = ForeignKeyField('self', backref='recommended',
+                                    column_name='recommendedby', null=True)
+    joindate = DateTimeField()
+
+    class Meta:
+        table_name = 'members'
+
+
+# Conveniently declare decimal fields suitable for storing currency.
+MoneyField = partial(DecimalField, decimal_places=2)
+
+
+class Facility(BaseModel):
+    facid = AutoField()
+    name = CharField()
+    membercost = MoneyField()
+    guestcost = MoneyField()
+    initialoutlay = MoneyField()
+    monthlymaintenance = MoneyField()
+
+    class Meta:
+        table_name = 'facilities'
+
+
+class Booking(BaseModel):
+    bookid = AutoField()
+    facility = ForeignKeyField(Facility, column_name='facid')
+    member = ForeignKeyField(Member, column_name='memid')
+    starttime = DateTimeField()
+    slots = IntegerField()
+
+    class Meta:
+        table_name = 'bookings'