Python meetup demo

main.ipynb

{
 "cells": [
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "## Basic usage"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "DEMO project used in this notebook: github.com/scylladb/care-pet"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 12,
   "metadata": {},
   "outputs": [],
   "source": [
    "from cassandra.cluster import Cluster"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 13,
   "metadata": {},
   "outputs": [
    {
     "data": {
      "text/plain": [
       "<cassandra.cluster.Session at 0x7ffab0778be0>"
      ]
     },
     "execution_count": 13,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "# basic example\n",
    "cluster = Cluster(['172.25.0.3'])\n",
    "session = cluster.connect()\n",
    "\n",
    "session"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 14,
   "metadata": {},
   "outputs": [
    {
     "name": "stdout",
     "output_type": "stream",
     "text": [
      "[Row(owner_id=UUID('8c32db47-c776-44fe-a62e-b2031687c1be'), address='home', name='Martin Elliott')]\n"
     ]
    }
   ],
   "source": [
    "# query data\n",
    "query = \"SELECT * FROM carepet.owner LIMIT 5\"\n",
    "result = session.execute(query).all()\n",
    "print(result)"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 15,
   "metadata": {},
   "outputs": [
    {
     "name": "stdout",
     "output_type": "stream",
     "text": [
      "8c32db47-c776-44fe-a62e-b2031687c1be home Martin Elliott\n"
     ]
    }
   ],
   "source": [
    "for row in result:\n",
    "    print(row.owner_id, row.address, row.name)"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 16,
   "metadata": {},
   "outputs": [
    {
     "data": {
      "text/plain": [
       "<cassandra.cluster.ResultSet at 0x7ffab07780d0>"
      ]
     },
     "execution_count": 16,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "# insert data\n",
    "import uuid\n",
    "\n",
    "columns = \",\".join([\"owner_id\", \"address\", \"name\"])\n",
    "new_owner_id = uuid.uuid4()\n",
    "values = [new_owner_id, \"742 Evergreen Terrace, Springfield\", \"Homer Simpson\"]\n",
    "insert_query = f\"\"\"\n",
    "    INSERT INTO carepet.owner ({ columns })\n",
    "    VALUES (%s, %s, %s);\n",
    "\"\"\"\n",
    "session.execute(insert_query, values)"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 19,
   "metadata": {},
   "outputs": [
    {
     "name": "stdout",
     "output_type": "stream",
     "text": [
      "None\n"
     ]
    }
   ],
   "source": [
    "# check new inserted row\n",
    "query = \"SELECT * FROM carepet.owner WHERE owner_id = %s;\"\n",
    "params = [new_owner_id]\n",
    "result = session.execute(query, params).one()\n",
    "print(result)"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 18,
   "metadata": {},
   "outputs": [
    {
     "data": {
      "text/plain": [
       "<cassandra.cluster.ResultSet at 0x7ffacccd7c10>"
      ]
     },
     "execution_count": 18,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "# delete data\n",
    "query = \"DELETE FROM carepet.owner WHERE owner_id=%s\"\n",
    "session.execute(query, [new_owner_id])"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "## Execution profile"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 20,
   "metadata": {},
   "outputs": [],
   "source": [
    "from cassandra.cluster import Cluster, ExecutionProfile, EXEC_PROFILE_DEFAULT, ConsistencyLevel\n",
    "from cassandra.query import dict_factory"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 21,
   "metadata": {},
   "outputs": [
    {
     "data": {
      "text/plain": [
       "<cassandra.cluster.Session at 0x7ffab0619a50>"
      ]
     },
     "execution_count": 21,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "# connect using execution profile\n",
    "profile = ExecutionProfile(\n",
    "            consistency_level=ConsistencyLevel.LOCAL_QUORUM,\n",
    "            row_factory=dict_factory\n",
    "        )\n",
    "\n",
    "cluster = Cluster(['172.25.0.3'], execution_profiles={EXEC_PROFILE_DEFAULT: profile})\n",
    "session = cluster.connect(keyspace=\"carepet\")\n",
    "\n",
    "session"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 22,
   "metadata": {},
   "outputs": [
    {
     "name": "stdout",
     "output_type": "stream",
     "text": [
      "[{'owner_id': UUID('8c32db47-c776-44fe-a62e-b2031687c1be'), 'address': 'home', 'name': 'Martin Elliott'}]\n"
     ]
    }
   ],
   "source": [
    "# query result is a list of dictionaries\n",
    "query = \"SELECT * FROM owner LIMIT 5\"\n",
    "result = session.execute(query).all()\n",
    "print(result)"
   ]
  }
 ],
 "metadata": {
  "kernelspec": {
   "display_name": "env",
   "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": "3.10.12"
  },
  "orig_nbformat": 4
 },
 "nbformat": 4,
 "nbformat_minor": 2
}