diff --git a/config.py b/config.py
index ad2a9b1..3c3531a 100644
--- a/config.py
+++ b/config.py
@@ -1,21 +1,17 @@
 import os
 from pathlib import Path
+from urllib.parse import quote_plus
 from dotenv import load_dotenv
 
 BASE_DIR = Path(__file__).resolve().parent
 load_dotenv(BASE_DIR / '.env')
 
 
-def _normalize_sqlalchemy_db_url(raw: str | None) -> str:
-    if raw:
-        raw = raw.strip()
-        if raw.startswith('postgres://'):
-            return raw.replace('postgres://', 'postgresql+psycopg://', 1)
-        if raw.startswith('sqlite:///') and not raw.startswith('sqlite:////'):
-            rel = raw.replace('sqlite:///', '', 1)
-            return f"sqlite:///{(BASE_DIR / rel).resolve()}"
-        return raw
+def _q(value: str) -> str:
+    return quote_plus(value or '')
 
+
+def _build_db_url() -> str:
     db_engine = os.getenv('DB_ENGINE', 'sqlite').strip().lower()
     db_host = os.getenv('DB_HOST', 'localhost').strip()
     db_port = os.getenv('DB_PORT', '').strip()
@@ -28,11 +24,17 @@ def _normalize_sqlalchemy_db_url(raw: str | None) -> str:
 
     if db_engine in ('pgsql', 'postgres', 'postgresql'):
         port = db_port or '5432'
-        return f"postgresql+psycopg://{db_user}:{db_password}@{db_host}:{port}/{db_name}"
+        return (
+            f"postgresql+psycopg://{_q(db_user)}:{_q(db_password)}"
+            f"@{db_host}:{port}/{_q(db_name)}"
+        )
 
     if db_engine == 'mysql':
         port = db_port or '3306'
-        return f"mysql+pymysql://{db_user}:{db_password}@{db_host}:{port}/{db_name}"
+        return (
+            f"mysql+pymysql://{_q(db_user)}:{_q(db_password)}"
+            f"@{db_host}:{port}/{_q(db_name)}"
+        )
 
     raise ValueError(f"Nieobsługiwany DB_ENGINE: {db_engine}")
 
@@ -57,7 +59,7 @@ def _normalize_redis_url(raw: str | None) -> str:
 class Config:
     SECRET_KEY = os.getenv('SECRET_KEY', 'change-me-please')
     APP_MASTER_KEY = os.getenv('APP_MASTER_KEY', SECRET_KEY)
-    SQLALCHEMY_DATABASE_URI = _normalize_sqlalchemy_db_url(os.getenv('DATABASE_URL'))
+    SQLALCHEMY_DATABASE_URI = _build_db_url()
     SQLALCHEMY_TRACK_MODIFICATIONS = False
     ARCHIVE_PATH = _path_from_env('ARCHIVE_PATH', BASE_DIR / 'storage' / 'archive')
     PDF_PATH = _path_from_env('PDF_PATH', BASE_DIR / 'storage' / 'pdf')
@@ -77,8 +79,6 @@ class Config:
     SESSION_COOKIE_HTTPONLY = True
     REMEMBER_COOKIE_HTTPONLY = True
     SESSION_COOKIE_SAMESITE = 'Lax'
-    #CEIDG_API_URL = os.getenv('CEIDG_API_URL', 'https://dane.biznes.gov.pl/api/ceidg/v2/firmy')
-    #CEIDG_TEST_API_URL = os.getenv('CEIDG_TEST_API_URL', 'https://test-dane.biznes.gov.pl/api/ceidg/v2/firmy')
     APP_FOOTER_TEXT = 'KSeF Manager · linuxiarz.pl · Mateusz Gruszczyński'
 
 
@@ -87,4 +87,4 @@ class TestConfig(Config):
     WTF_CSRF_ENABLED = False
     SQLALCHEMY_DATABASE_URI = 'sqlite:///:memory:'
     REDIS_URL = 'memory://'
-    RATELIMIT_STORAGE_URI = 'memory://'
+    RATELIMIT_STORAGE_URI = 'memory://'
\ No newline at end of file