fixes to postgres issue

cognee/infrastructure/databases/relational/create_relational_engine.py

@@ -39,8 +39,15 @@ def create_relational_engine(
         connection_string = f"sqlite+aiosqlite:///{db_path}/{db_name}"
 
     if db_provider == "postgres":
-        connection_string = (
-            f"postgresql+asyncpg://{db_username}:{db_password}@{db_host}:{db_port}/{db_name}"
-        )
+        try:
+            # Test if asyncpg is available
+            import asyncpg
+            connection_string = (
+                f"postgresql+asyncpg://{db_username}:{db_password}@{db_host}:{db_port}/{db_name}"
+            )
+        except ImportError:
+            raise ImportError(
+                "PostgreSQL dependencies are not installed. Please install with 'pip install cognee[postgres]' or 'pip install cognee[postgres-binary]' to use PostgreSQL functionality."
+            )
 
     return SQLAlchemyAdapter(connection_string)

cognee/infrastructure/databases/vector/pgvector/PGVectorAdapter.py

@@ -7,7 +7,16 @@ from sqlalchemy import JSON, Column, Table, select, delete, MetaData
 from sqlalchemy.ext.asyncio import create_async_engine, async_sessionmaker
 from sqlalchemy.exc import ProgrammingError
 from tenacity import retry, retry_if_exception_type, stop_after_attempt, wait_exponential
-from asyncpg import DeadlockDetectedError, DuplicateTableError, UniqueViolationError
+try:
+    from asyncpg import DeadlockDetectedError, DuplicateTableError, UniqueViolationError
+except ImportError:
+    # PostgreSQL dependencies not installed, define dummy exceptions
+    class DeadlockDetectedError(Exception):
+        pass
+    class DuplicateTableError(Exception):
+        pass
+    class UniqueViolationError(Exception):
+        pass
 
 
 from cognee.shared.logging_utils import get_logger
@@ -70,9 +79,13 @@ class PGVectorAdapter(SQLAlchemyAdapter, VectorDBInterface):
 
         # Has to be imported at class level
         # Functions reading tables from database need to know what a Vector column type is
-        from pgvector.sqlalchemy import Vector
-
-        self.Vector = Vector
+        try:
+            from pgvector.sqlalchemy import Vector
+            self.Vector = Vector
+        except ImportError:
+            raise ImportError(
+                "PostgreSQL dependencies are not installed. Please install with 'pip install cognee[postgres]' or 'pip install cognee[postgres-binary]' to use PGVector functionality."
+            )
 
     async def embed_data(self, data: list[str]) -> list[list[float]]:
         """

pyproject.toml

@@ -72,15 +72,18 @@ distributed = [
     "modal>=1.0.5,<2.0.0",
 ]
 
+# Database backends
 neo4j = ["neo4j>=5.28.0,<6"]
 neptune = ["langchain_aws>=0.2.22"]
+# PostgreSQL support (binary - no compilation required)
 postgres = [
-    "psycopg2>=2.9.10,<3",
+    "psycopg2-binary>=2.9.10,<3.0.0",  # Pre-compiled binary, no PostgreSQL headers needed
     "pgvector>=0.3.5,<0.4",
     "asyncpg>=0.30.0,<1.0.0",
 ]
-postgres-binary = [
-    "psycopg2-binary>=2.9.10,<3.0.0",
+# PostgreSQL support (source - requires PostgreSQL development headers)
+postgres-source = [
+    "psycopg2>=2.9.10,<3 ; platform_system != 'Windows'",  # Requires libpq-dev, build tools
     "pgvector>=0.3.5,<0.4",
     "asyncpg>=0.30.0,<1.0.0",
 ]