move to postgresql

core/db/connection.py

@@ -0,0 +1,33 @@
+"""
+Database engine and session — SQLModel/SQLAlchemy, no Django.
+
+Reads DATABASE_URL from the environment.
+"""
+
+from __future__ import annotations
+
+import os
+
+from sqlalchemy import create_engine
+from sqlmodel import Session
+
+DATABASE_URL = os.environ.get("DATABASE_URL", "postgresql://mpr:mpr@localhost:5432/mpr")
+
+_engine = None
+
+
+def get_engine():
+    global _engine
+    if _engine is None:
+        _engine = create_engine(DATABASE_URL, pool_size=5, max_overflow=10)
+    return _engine
+
+
+def get_session() -> Session:
+    return Session(get_engine())
+
+
+def create_tables():
+    """Create all SQLModel tables."""
+    from .models import SQLModel  # noqa — registers all models
+    SQLModel.metadata.create_all(get_engine())