diff --git a/.gitignore b/.gitignore
new file mode 100644
index 0000000..2eea525
--- /dev/null
+++ b/.gitignore
@@ -0,0 +1 @@
+.env
\ No newline at end of file
diff --git a/README.md b/README.md
index b0ef389..b11157b 100644
--- a/README.md
+++ b/README.md
@@ -16,7 +16,7 @@
   <br>
   <hr> 
 
-</details>
+</details>v
 
 <details>
   <summary>
diff --git a/connection.ipynb b/connection.ipynb
new file mode 100644
index 0000000..ec9d958
--- /dev/null
+++ b/connection.ipynb
@@ -0,0 +1,215 @@
+{
+ "cells": [
+  {
+   "cell_type": "code",
+   "execution_count": 1,
+   "id": "081e20bf",
+   "metadata": {},
+   "outputs": [],
+   "source": [
+    "import os\n",
+    "import pandas as pd\n",
+    "from sqlalchemy import create_engine\n",
+    "from dotenv import load_dotenv\n",
+    "\n",
+    "load_dotenv(\".env\")  # carga tu contraseña u otros secretos\n",
+    "\n",
+    "USER = \"root\"\n",
+    "PASSWORD = os.getenv(\"Key\")\n",
+    "HOST = \"localhost\"\n",
+    "PORT = \"3306\"\n",
+    "DB_NAME = \"sakila\"\n",
+    "\n",
+    "engine = create_engine(f\"mysql+pymysql://{USER}:{PASSWORD}@{HOST}:{PORT}/{DB_NAME}\")"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": null,
+   "id": "c3ba4755",
+   "metadata": {},
+   "outputs": [],
+   "source": [
+    "# Funcion rentals month\n",
+    "def rentals_month(engine, month, year):\n",
+    "    \"\"\"\n",
+    "    Recupera todos los alquileres del mes y año especificados.\n",
+    "    \"\"\"\n",
+    "    query = f\"\"\"\n",
+    "        SELECT *\n",
+    "        FROM rental\n",
+    "        WHERE MONTH(rental_date) = {month}\n",
+    "          AND YEAR(rental_date) = {year};\n",
+    "    \"\"\"\n",
+    "    df = pd.read_sql(query, engine)\n",
+    "    return df\n"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": null,
+   "id": "2e2a2926",
+   "metadata": {},
+   "outputs": [],
+   "source": [
+    "# Funcion rental_count_month\n",
+    "def rental_count_month(df, month, year):\n",
+    "    \"\"\"\n",
+    "    Devuelve un DataFrame con el número total de alquileres por cliente.\n",
+    "    \"\"\"\n",
+    "    col_name = f\"alquileres_{month:02d}_{year}\"\n",
+    "\n",
+    "    df_counts = (\n",
+    "        df.groupby(\"customer_id\")\n",
+    "          .size()\n",
+    "          .reset_index(name=col_name)\n",
+    "    )\n",
+    "\n",
+    "    return df_counts\n"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": null,
+   "id": "6263cb5f",
+   "metadata": {},
+   "outputs": [],
+   "source": [
+    "# Funcion compare_rentals\n",
+    "def compare_rentals(df1, df2):\n",
+    "    \"\"\"\n",
+    "    Combina dos DataFrames de conteo de alquileres por cliente\n",
+    "    y calcula la diferencia entre ambos meses.\n",
+    "    \"\"\"\n",
+    "    df_merged = pd.merge(df1, df2, on=\"customer_id\", how=\"outer\").fillna(0)\n",
+    "\n",
+    "    col1 = df1.columns[1]\n",
+    "    col2 = df2.columns[1]\n",
+    "\n",
+    "    df_merged[\"diferencia\"] = df_merged[col2] - df_merged[col1]\n",
+    "\n",
+    "    return df_merged\n"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": null,
+   "id": "91fba459",
+   "metadata": {},
+   "outputs": [
+    {
+     "data": {
+      "text/html": [
+       "<div>\n",
+       "<style scoped>\n",
+       "    .dataframe tbody tr th:only-of-type {\n",
+       "        vertical-align: middle;\n",
+       "    }\n",
+       "\n",
+       "    .dataframe tbody tr th {\n",
+       "        vertical-align: top;\n",
+       "    }\n",
+       "\n",
+       "    .dataframe thead th {\n",
+       "        text-align: right;\n",
+       "    }\n",
+       "</style>\n",
+       "<table border=\"1\" class=\"dataframe\">\n",
+       "  <thead>\n",
+       "    <tr style=\"text-align: right;\">\n",
+       "      <th></th>\n",
+       "      <th>customer_id</th>\n",
+       "      <th>alquileres_05_2005</th>\n",
+       "      <th>alquileres_06_2005</th>\n",
+       "      <th>diferencia</th>\n",
+       "    </tr>\n",
+       "  </thead>\n",
+       "  <tbody>\n",
+       "    <tr>\n",
+       "      <th>0</th>\n",
+       "      <td>1</td>\n",
+       "      <td>2.0</td>\n",
+       "      <td>7.0</td>\n",
+       "      <td>5.0</td>\n",
+       "    </tr>\n",
+       "    <tr>\n",
+       "      <th>1</th>\n",
+       "      <td>2</td>\n",
+       "      <td>1.0</td>\n",
+       "      <td>1.0</td>\n",
+       "      <td>0.0</td>\n",
+       "    </tr>\n",
+       "    <tr>\n",
+       "      <th>2</th>\n",
+       "      <td>3</td>\n",
+       "      <td>2.0</td>\n",
+       "      <td>4.0</td>\n",
+       "      <td>2.0</td>\n",
+       "    </tr>\n",
+       "    <tr>\n",
+       "      <th>3</th>\n",
+       "      <td>4</td>\n",
+       "      <td>0.0</td>\n",
+       "      <td>6.0</td>\n",
+       "      <td>6.0</td>\n",
+       "    </tr>\n",
+       "    <tr>\n",
+       "      <th>4</th>\n",
+       "      <td>5</td>\n",
+       "      <td>3.0</td>\n",
+       "      <td>5.0</td>\n",
+       "      <td>2.0</td>\n",
+       "    </tr>\n",
+       "  </tbody>\n",
+       "</table>\n",
+       "</div>"
+      ],
+      "text/plain": [
+       "   customer_id  alquileres_05_2005  alquileres_06_2005  diferencia\n",
+       "0            1                 2.0                 7.0         5.0\n",
+       "1            2                 1.0                 1.0         0.0\n",
+       "2            3                 2.0                 4.0         2.0\n",
+       "3            4                 0.0                 6.0         6.0\n",
+       "4            5                 3.0                 5.0         2.0"
+      ]
+     },
+     "execution_count": 5,
+     "metadata": {},
+     "output_type": "execute_result"
+    }
+   ],
+   "source": [
+    "# Check\n",
+    "df_may = rentals_month(engine, 5, 2005)\n",
+    "df_jun = rentals_month(engine, 6, 2005)\n",
+    "\n",
+    "count_may = rental_count_month(df_may, 5, 2005)\n",
+    "count_jun = rental_count_month(df_jun, 6, 2005)\n",
+    "\n",
+    "comparison = compare_rentals(count_may, count_jun)\n",
+    "comparison.head()\n"
+   ]
+  }
+ ],
+ "metadata": {
+  "kernelspec": {
+   "display_name": "Python 3",
+   "language": "python",
+   "name": "python3"
+  },
+  "language_info": {
+   "codemirror_mode": {
+    "name": "ipython",
+    "version": 3
+   },
+   "file_extension": ".py",
+   "mimetype": "text/x-python",
+   "name": "python",
+   "nbconvert_exporter": "python",
+   "pygments_lexer": "ipython3",
+   "version": "3.12.9"
+  }
+ },
+ "nbformat": 4,
+ "nbformat_minor": 5
+}