[main] Updated models to reflect current constraints

src/models/book_category_link.py

@@ -8,8 +8,8 @@ from .base import Base
 class BookCategoryLink(Base):
     __tablename__ = 'book_category_link'
 
-    book_id          = Column(Integer, ForeignKey('book.id'), primary_key=True)
+    book_id          = Column(Integer, ForeignKey('book.id', ondelete="cascade"), primary_key=True)
-    book_category_id = Column(Integer, ForeignKey('book_category.id'), primary_key=True)
+    book_category_id = Column(Integer, ForeignKey('book_category.id', ondelete="cascade"), primary_key=True)
 
     book          = relationship('Book', overlaps='categories,books')
     book_category = relationship('BookCategory', overlaps='categories,books')

src/models/member.py

@@ -19,7 +19,7 @@ class Member(Base):
     first_name    = Column(String(50), nullable=False)
     last_name     = Column(String(50), nullable=False)
     email         = Column(String(100), nullable=False, unique=True)
-    phone         = Column(String(20), nullable=True)
+    phone         = Column(String(20), nullable=True, unique=True)
     register_date = Column(TIMESTAMP, nullable=True, server_default=func.now())
     status        = Column(Enum(MemberStatusEnum), nullable=True, default=MemberStatusEnum.active)
     last_updated  = Column(TIMESTAMP, nullable=True)