TSML: Improve timeseries-anomaly-detection.ipynb notebook

- Use `REFRESH TABLE` to synchronize data
- Improve formatting around `CONNECTION_STRING`

Author: amotl

topic/timeseries/timeseries-anomaly-detection.ipynb

@@ -88,7 +88,7 @@
     "In this step, we will create the table and populate it with the dataset from [nab-machine-failure.csv]. If you are using CrateDB Cloud, you can use the [URL import] available in the console, otherwise, use the `COPY FROM` statement used below. You can run it in the console in the Admin UI or you can use [Crash], in this case, we are using SQLAlchemy.\n",
     "\n",
     "[URL import]: https://cratedb.com/docs/cloud/en/latest/reference/overview.html#import-from-url\n",
-    "[nab-machine-failure.csv]: https://github.com/crate/cratedb-datasets/raw/main/timeseries/nab-machine-failure.csv\",\n",
+    "[nab-machine-failure.csv]: https://github.com/crate/cratedb-datasets/raw/main/timeseries/nab-machine-failure.csv\n",
     "[Crash]: https://cratedb.com/docs/crate/crash/en/latest/getting-started.html"
    ]
   },
@@ -98,25 +98,22 @@
    "metadata": {},
    "outputs": [],
    "source": [
-    "# Use this connection string template for CrateDB Cloud Clusters\n",
+    "# crate://<USER>:<PASSWORD>@<HOST>\n",
     "CONNECTION_STRING = os.environ.get(\n",
     "     \"CRATEDB_CONNECTION_STRING\",\n",
-    "     \"crate://<USER>:<PASSWORD>@<HOST>\",\n",
-    ")\n",
-    "\n",
-    "# Use this connection string template for CrateDB running locally\n",
-    "#CONNECTION_STRING = os.environ.get(\n",
-    "#     \"CRATEDB_CONNECTION_STRING\",\n",
-    "#     \"crate://localhost:4200\",\n",
-    "# )\n",
+    "     \"crate://localhost:4200\",\n",
+    " )\n",
     "\n",
     "engine = sa.create_engine(CONNECTION_STRING, echo=os.environ.get('DEBUG'))\n",
     "\n",
-    "query_create_table = 'CREATE TABLE machine_data (\"timestamp\" TIMESTAMP, \"value\" DOUBLE PRECISION)' \n",
-    "query_copy_from = \"COPY machine_data FROM 'https://github.com/crate/cratedb-datasets/raw/main/timeseries/nab-machine-failure.csv';\"\n",
+    "sql_ddl = 'CREATE TABLE machine_data (\"timestamp\" TIMESTAMP, \"value\" DOUBLE PRECISION)'\n",
+    "sql_load = \"COPY machine_data FROM 'https://github.com/crate/cratedb-datasets/raw/main/timeseries/nab-machine-failure.csv';\"\n",
+    "sql_refresh = \"REFRESH TABLE machine_data;\"\n",
+    "\n",
     "with engine.connect() as conn:\n",
-    "    conn.execute(sa.text(query_create_table))\n",
-    "    conn.execute(sa.text(query_copy_from))\n"
+    "    conn.execute(sa.text(sql_ddl))\n",
+    "    conn.execute(sa.text(sql_load))\n",
+    "    conn.execute(sa.text(sql_refresh))"
    ]
   },
   {