crewAIInc/crewAI · error · ValueError

Database name is required in the URI

Error message

Database name is required in the URI

What it means

Raised by MySQLLoader.load() when the db_uri parses but contains no database name — parsed.path is empty or only slashes, so database becomes None/empty after lstrip('/'). The loader requires the schema to be part of the URI because pymysql connects to a specific database and the code never issues USE.

Source

Thrown at lib/crewai-tools/src/crewai_tools/rag/loaders/mysql_loader.py:49

        query = source.source

        parsed = urlparse(db_uri)
        if parsed.scheme not in ["mysql", "mysql+pymysql"]:
            raise ValueError(f"Invalid MySQL URI scheme: {parsed.scheme}")

        connection_params = {
            "host": parsed.hostname or "localhost",
            "port": parsed.port or 3306,
            "user": parsed.username,
            "password": parsed.password,
            "database": parsed.path.lstrip("/") if parsed.path else None,
            "charset": "utf8mb4",
            "cursorclass": DictCursor,
        }

        if not connection_params["database"]:
            raise ValueError("Database name is required in the URI")

        try:
            connection = connect(**connection_params)
            try:
                with connection.cursor() as cursor:
                    cursor.execute(query)
                    rows = cursor.fetchall()

                    if not rows:
                        content = "No data found in the table"
                        return LoaderResult(
                            content=content,
                            metadata={"source": query, "row_count": 0},
                            doc_id=self.generate_doc_id(
                                source_ref=query, content=content
                            ),
                        )

View on GitHub (pinned to 754d7323be)

Solutions

1. Append the database name to the URI: mysql://user:pass@host:3306/mydatabase.
2. Build the URI from parts with a check that db is non-empty before composing the string.
3. If the database name contains special characters, URL-encode it so the path still parses.

Example fix

# before
result = MySQLLoader().load(src, metadata={'db_uri': 'mysql://u:p@h:3306'})

# after
result = MySQLLoader().load(src, metadata={'db_uri': 'mysql://u:p@h:3306/app_db'})

from urllib.parse import urlparse\n\ndef uri_has_database(uri: str) -> bool:\n    return bool(urlparse(uri).path.lstrip('/'))

When it happens

Trigger: Passing 'mysql://user:pass@host:3306' (no /dbname); 'mysql://user:pass@host:3306/' (trailing slash only); URIs where the path segment was lost during templating or URL-encoding.

Common situations: Storing server coordinates in config and expecting the loader to take the database from a separate key; templating bugs that render an empty database placeholder (mysql://u:p@h:3306/); copy-paste from connection strings used by GUI clients that keep the database in a separate field.

Related errors

• Database URI is required for MySQL loader
• Invalid MySQL URI scheme: {parsed.scheme}
• Project name cannot be empty
• Project name '{name}' produces invalid folder name '{folder_
• No deployable project files were found.

AI-assisted analysis of crewAIInc/crewAI@754d7323be (2026-08-15). Data as JSON: /api/errors/cc74c384653fe650. Report an issue: GitHub.