diff --git a/sum23/lecture_materials/23_Plotting2/Exam Review.ipynb b/sum23/lecture_materials/23_Plotting2/Exam Review.ipynb
index 226bbbbf1a01148c59613622e6942f106540cdbd..f74342769b636570c12a9f678a3ce9026702bf86 100644
--- a/sum23/lecture_materials/23_Plotting2/Exam Review.ipynb	
+++ b/sum23/lecture_materials/23_Plotting2/Exam Review.ipynb	
@@ -8,16 +8,18 @@
    "outputs": [],
    "source": [
     "import pandas as pd\n",
-    "from bs4 import BeautifulSoup"
+    "from bs4 import BeautifulSoup\n",
+    "import sqlite3"
    ]
   },
   {
-   "cell_type": "code",
-   "execution_count": null,
-   "id": "0c34e6b0",
+   "cell_type": "markdown",
+   "id": "5c9d1d79",
    "metadata": {},
-   "outputs": [],
-   "source": []
+   "source": [
+    "# Big picture review\n",
+    "Series vs dataframe vs database"
+   ]
   },
   {
    "cell_type": "code",
@@ -202,6 +204,45 @@
     "# get_text, children, attrs"
    ]
   },
+  {
+   "cell_type": "markdown",
+   "id": "753cf273",
+   "metadata": {},
+   "source": [
+    "# Databases"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": null,
+   "id": "4fda7cf8",
+   "metadata": {},
+   "outputs": [],
+   "source": [
+    "assert os.path.exists(\"movies.db\")\n",
+    "conn = sqlite3.connect(\"movies.db\")\n",
+    "\n",
+    "def qry(QUERY):\n",
+    "    '''QUERY is a string containing SQL, conn is a global connection variable'''\n",
+    "    return pd.read_sql(QUERY, conn)"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "id": "f98c2f0c",
+   "metadata": {},
+   "source": [
+    "where vs having"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": null,
+   "id": "a76a21e2",
+   "metadata": {},
+   "outputs": [],
+   "source": []
+  },
   {
    "cell_type": "markdown",
    "id": "984915b2",
diff --git a/sum23/lecture_materials/23_Plotting2/movies.db b/sum23/lecture_materials/23_Plotting2/movies.db
new file mode 100644
index 0000000000000000000000000000000000000000..f5c27f4492ff76e2297f92a520d500027cf7c273
Binary files /dev/null and b/sum23/lecture_materials/23_Plotting2/movies.db differ