diff --git a/collectionObj/models.py b/collectionObj/models.py
index ef6c257..5ddc1d7 100644
--- a/collectionObj/models.py
+++ b/collectionObj/models.py
@@ -1,22 +1,43 @@
-from fastapi import HTTPException
-from sqlalchemy import Column, Integer, String, Float, Boolean, ForeignKey
-from sqlalchemy.dialects.postgresql import ARRAY
+from fastapi import HTTPException, Depends
+from sqlalchemy import Integer, String, Boolean
+from pydantic import BaseModel
 from sqlalchemy.orm import Session, relationship, mapped_column, Mapped
 from ..config import Base, get_session_db, user_collection, collection_item
+from ..auth.models import DBUser
 from typing import TYPE_CHECKING
 
 if TYPE_CHECKING:
-    from ..auth.models import DBUser
-    from ..items.models import Items
+    from ..items.models import Items, Item
+    
+    
 
 
+###### SCHEMAS #########
 
+class CollectionBase(BaseModel):
+    collection_name : str | None = None
+    collection_description : str | None = None
+    visibility : bool | None = None
+
+class CollectionCreate(CollectionBase):
+    pass
+
+class CollectionPublic(CollectionBase):
+    collection_id : int | None = None
+
+    class Config:
+        from_attributes = True #sqlalchemy ile pydantic arasında geçiş yapabilmek için kullanılır
+
+class CollectionUpdate(CollectionBase):
+    pass
+
+    
 
 ##### veri tabanı modelleri #####
 class CollectionsDB(Base):
     __tablename__ = "collections_table"
 
-    collection_id : Mapped[int] = mapped_column(Integer, primary_key=True)
+    collection_id : Mapped[int] = mapped_column(Integer, primary_key=True, index=True, autoincrement=True)
     #user_id : Mapped[int] = mapped_column(Integer, ForeignKey("users_table.user_id"), nullable=False) # user_id ile ilişki
     #item_id : Mapped[list[int]] = mapped_column(Integer, ForeignKey("items_table.item_id"), nullable=False) # item_id ile ilişki
     visibility : Mapped[bool] = mapped_column(Boolean, default=True)
@@ -24,7 +45,7 @@ class CollectionsDB(Base):
     collection_description : Mapped[str] = mapped_column(String, default="No description")
 
     # ilişkiler
-    users : Mapped['DBUser'] = relationship(
+    users : Mapped[list['DBUser']] = relationship(
         "DBUser",
         secondary=user_collection, 
         back_populates="collections", 
@@ -39,4 +60,114 @@ class CollectionsDB(Base):
     )
 
 
-    #### collection bir item listesi birde kullanıcı listesi tutacak 
\ No newline at end of file
+    #### collection bir item listesi birde kullanıcı listesi tutacak 
+
+
+
+def create_colletion(
+        collection: CollectionCreate | None = None,
+        user_id : int | None = None
+
+) -> bool:
+    """
+    Collection oluşturma fonksiyonu
+    """
+    if collection is None:
+        raise HTTPException(status_code=400, detail="Collection is None returned")
+    
+    session = next(get_session_db()) # -> get_session_db() fonksiyonu daima generator döndürür next ile çağırmalısın
+    user = session.query(DBUser).filter(DBUser.user_id == user_id).first()
+    if user is None:
+        raise HTTPException(status_code=404, detail="User not found")
+    
+
+    try: 
+        new_collection = CollectionsDB(
+            collection_name=collection.collection_name,
+            collection_description=collection.collection_description,
+            visibility=collection.visibility
+        )
+
+        new_collection.users.append(user)
+        session.add(new_collection)
+        session.commit()
+    except Exception as e:
+        raise HTTPException(status_code=500, detail=f"Error creating collection: {e}")
+    
+    return True
+
+
+def get_collections(
+        user_id : int | None = None
+) -> list[CollectionPublic] | None:
+    """
+    Kullanıcının collectionlarını döndürür
+    """
+    if user_id is None:
+        raise HTTPException(status_code=400, detail="User id is None")
+    
+    session = next(get_session_db()) # -> get_session_db() fonksiyonu daima generator döndürür next ile çağırmalısın
+    collections = session.query(CollectionsDB).filter(CollectionsDB.users.any(user_id=user_id)).all()
+    
+    if collections is None:
+        raise HTTPException(status_code=404, detail="No collections found")
+    
+    return collections
+
+def update_collection(
+        collection: CollectionUpdate | None = None,
+        user_id : int | None = None,
+        collection_id : int | None = None
+) -> bool:
+    """
+    Collection güncelleme fonksiyonu
+    """
+    if collection is None:
+        raise HTTPException(status_code=400, detail="Collection is None returned")
+    
+    session = next(get_session_db()) # -> get_session_db() fonksiyonu daima generator döndürür next ile çağırmalısın
+    user = session.query(DBUser).filter(DBUser.user_id == user_id).first()
+    if user is None:
+        raise HTTPException(status_code=404, detail="User not found")
+    
+    collection_to_update = session.query(CollectionsDB).filter(CollectionsDB.collection_id == collection_id).first()
+    if collection_to_update is None:
+        raise HTTPException(status_code=404, detail="Collection not found")
+    
+    try:
+        collection_to_update.collection_name = collection.collection_name
+        collection_to_update.collection_description = collection.collection_description
+        collection_to_update.visibility = collection.visibility
+
+        session.commit()
+    except Exception as e:
+        raise HTTPException(status_code=500, detail=f"Error updating collection: {e}")
+    
+    return True
+
+def delete_collection(
+        user_id : int | None = None,
+        collection_id : int | None = None
+) -> bool:
+    """
+    Collection silme fonksiyonu
+    """
+    if user_id is None or collection_id is None:
+        raise HTTPException(status_code=400, detail="User id or collection id is None")
+    
+    session = next(get_session_db()) # -> get_session_db() fonksiyonu daima generator döndürür next ile çağırmalısın
+    user = session.query(DBUser).filter(DBUser.user_id == user_id).first()
+    if user is None:
+        raise HTTPException(status_code=404, detail="User not found")
+    
+    collection_to_delete = session.query(CollectionsDB).filter(CollectionsDB.collection_id == collection_id).first()
+    if collection_to_delete is None:
+        raise HTTPException(status_code=404, detail="Collection not found")
+    
+    try:
+        session.delete(collection_to_delete)
+        session.commit()
+    except Exception as e:
+        raise HTTPException(status_code=500, detail=f"Error deleting collection: {e}")
+    
+    return True
\ No newline at end of file
diff --git a/collectionObj/router.py b/collectionObj/router.py
index 72387ea..f258273 100644
--- a/collectionObj/router.py
+++ b/collectionObj/router.py
@@ -1,8 +1,60 @@
 from fastapi import FastAPI, APIRouter
+from .models import CollectionPublic, CollectionCreate, CollectionUpdate
+from .models import get_collections, create_colletion, update_collection, delete_collection
 
 router = APIRouter(
     prefix="/collections",
     tags=["collections"],
     responses={404: {"description": "Not found"}},
     dependencies=[],
-)
\ No newline at end of file
+)
+
+
+
+@router.get("/{user_id}")
+async def get_collections_api(user_id: int) -> list[CollectionPublic]:
+    """
+    Kullanıcının collectionlarını döndürür
+    """
+
+    _collections : list[CollectionPublic] = get_collections(user_id=user_id)
+
+    return _collections
+
+
+
+@router.post("/{user_id}")
+async def create_collection(
+    user_id: int,
+    collection: CollectionCreate
+) -> bool:
+    """
+    Collection oluşturma fonksiyonu
+    """
+    _result = create_colletion(user_id=user_id, collection=collection)
+    return _result
+
+
+@router.put("/{user_id}/{collection_id}")
+async def update_collection_api(
+    user_id: int,
+    collection_id : int,
+    collection: CollectionUpdate
+) -> bool:
+    """
+    Collection güncelleme fonksiyonu
+    """
+    _result = update_collection(user_id=user_id, collection_id=collection_id, collection=collection)
+    return _result
+
+
+@router.delete("/{user_id}/{collection_id}")
+async def delete_collection_api(
+    user_id: int,
+    collection_id : int
+) -> bool:
+    """
+    Collection silme fonksiyonu
+    """
+    _result = delete_collection(user_id=user_id, collection_id=collection_id)
+    return _result
\ No newline at end of file
diff --git a/config.py b/config.py
index 2ab13c7..9657ba7 100644
--- a/config.py
+++ b/config.py
@@ -30,11 +30,11 @@ class Base(DeclarativeBase):
 #models te içe aktarmayı unutma
 
 def init_db():
-    Base.metadata.drop_all(engine)   # Veritabanını her başlangıcta siler burayada dikkat !!!!!!!!
+    #Base.metadata.drop_all(engine)   # Veritabanını her başlangıcta siler burayada dikkat !!!!!!!!
     Base.metadata.create_all(bind=engine) # Veritabanını oluşturur
 
 # Session dependency (FastAPI için)
-def get_session_db():
+def get_session_db() -> 'Generator[Session, None]':
     db = SessionLocal()
     try:
         yield db
diff --git a/items/models.py b/items/models.py
index b88a6a9..9adbf6d 100644
--- a/items/models.py
+++ b/items/models.py
@@ -70,10 +70,9 @@ class Items(Base):
     item_score: Mapped[float] = mapped_column(Float, default=0.0)
 
     # ilişkiler 
-    collections : Mapped['CollectionsDB']= relationship(
+    collections : Mapped[list['CollectionsDB']]= relationship(
         "CollectionsDB",
         secondary=collection_item,
         back_populates="items", 
         lazy='select'
     )  #back_populates karşı tarafın ismi
-    
\ No newline at end of file