2026-08-18T11:22:41  6 rows in 1ms       SELECT country, COUNT(*) FROM customers GROUP BY 1 LIMIT 201
2026-08-18T11:22:44  error: rejected     DELETE FROM customers

git clone https://github.com/dkautomation23/mcp-data-server.git
cd mcp-data-server
python -m venv .venv && . .venv/bin/activate      # Windows: .venv\Scripts\activate
pip install -r requirements.txt

python -m mcp_data_server.seed                    # creates demo.db
cp .env.example .env                              # then point DATABASE_PATH at your file
python -m mcp_data_server                         # serves over stdio

{
  "mcpServers": {
    "business-data": {
      "command": "python",
      "args": ["-m", "mcp_data_server"],
      "cwd": "C:/path/to/mcp-data-server",
      "env": {
        "DATABASE_PATH": "C:/path/to/your.db",
        "ALLOWED_TABLES": "customers,orders,order_items",
        "MASKED_COLUMNS": "customers.email,customers.phone"
      }
    }
  }
}

claude mcp add business-data -- python -m mcp_data_server

// run_sql("SELECT status, COUNT(*) n, ROUND(SUM(total_eur)) revenue FROM orders GROUP BY 1 ORDER BY 3 DESC")
{
  "sql": "SELECT status, COUNT(*) n, ROUND(SUM(total_eur)) revenue FROM orders GROUP BY 1 ORDER BY 3 DESC LIMIT 201",
  "columns": ["status", "n", "revenue"],
  "rows": [["paid", 92, 149914.0], ["pending", 39, 64596.0], ["refunded", 31, 45911.0]],
  "row_count": 3, "truncated": false, "elapsed_ms": 0
}

// run_sql("DELETE FROM customers")
{ "error": "only SELECT (or WITH ... SELECT) statements are allowed" }

// run_sql("SELECT * FROM internal_notes")
{ "error": "table 'internal_notes' is not in the allowlist (allowed: customers, orders, order_items)" }

// run_sql("SELECT id, name, email FROM customers LIMIT 2")
{ "rows": [[1, "Customer 001", "***"], [2, "Customer 002", "***"]] }

pytest -q

...............................                                          [100%]
31 passed in 1.77s