{
 "cells": [
  {
   "cell_type": "markdown",
   "id": "d1eece5a-dd1a-47c3-9596-399863ce1b37",
   "metadata": {},
   "source": [
    "# Fetch Records from a Database, *cont'd*"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": null,
   "id": "8c2769b7-ab08-4ad8-af36-6257935e2508",
   "metadata": {},
   "outputs": [],
   "source": [
    "from DATA225utils import make_connection"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": null,
   "id": "b6ef2857-2e78-497d-8422-4d27ae1b17a5",
   "metadata": {},
   "outputs": [],
   "source": [
    "conn = make_connection('school.ini')\n",
    "cursor = conn.cursor()"
   ]
  },
  {
   "cell_type": "markdown",
   "id": "cd1ebd70-9eaa-43e0-bddd-f9759315d5c3",
   "metadata": {},
   "source": [
    "#### Use `cursor.fetchmany(n)` to **fetch *n* rows** at a time. The last fetch may return fewer than *n* rows, or the empty list `[]`."
   ]
  },
  {
   "cell_type": "code",
   "execution_count": null,
   "id": "f8dadf35-ae54-4768-b649-8d954f556952",
   "metadata": {},
   "outputs": [],
   "source": [
    "sql = \"SELECT * FROM contact\";\n",
    "\n",
    "rows_per_fetch = 4  # Fetch 4 rows at a time.\n",
    "\n",
    "cursor.execute(sql);\n",
    "rows = cursor.fetchmany(rows_per_fetch)\n",
    "\n",
    "index = 1\n",
    "\n",
    "while rows != []:\n",
    "    for row in rows:\n",
    "        print(f'{index}: {row}')\n",
    "        index += 1\n",
    "\n",
    "    print(\"-----\")\n",
    "    rows = cursor.fetchmany(rows_per_fetch)"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": null,
   "id": "d39700ed-d498-4baa-8013-dbe6aa1b8aff",
   "metadata": {},
   "outputs": [],
   "source": [
    "cursor.close()\n",
    "conn.close()"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": null,
   "id": "bd846730-c1d1-4f3c-bcd3-368d48be3146",
   "metadata": {},
   "outputs": [],
   "source": [
    "# Copyright (c) 2023 by Ronald Mak"
   ]
  }
 ],
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   "display_name": "Python 3 (ipykernel)",
   "language": "python",
   "name": "python3"
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    "name": "ipython",
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