add postgres examples

notebooks/07_postgres_minimal.ipynb

@@ -0,0 +1,156 @@
+{
+ "cells": [
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "# Minimal Postgres Demo\n",
+    "\n",
+    "This notebook connects to the dockerized Postgres instance defined in `docker/docker-compose.yml`.\n",
+    "\n",
+    "Steps before running the cells:\n",
+    "\n",
+    "1. Start Postgres: `docker compose -f docker/docker-compose.yml up -d`.\n",
+    "2. Export environment variables so `sqlmodel_pg_kit` can locate the database (host defaults to `localhost` when run from the host).\n",
+    "   ```bash\n",
+    "   export SQL_HOST=localhost\n",
+    "   export SQL_PORT=5432\n",
+    "   export SQL_USER=appuser\n",
+    "   export SQL_PASSWORD=changeme\n",
+    "   export SQL_DATABASE=appdb\n",
+    "   export SQL_SSLMODE=disable\n",
+    "   ```\n",
+    "3. `pip install -e .` or `uv pip install .` from the project root.\n"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 1,
+   "id": "44df8c21",
+   "metadata": {},
+   "outputs": [],
+   "source": [
+    "from typing import Optional, List\n",
+    "import os\n",
+    "os.environ[\"SQL_HOST\"] = \"127.0.0.1\"\n",
+    "os.environ[\"SQL_PORT\"] = \"5432\"\n",
+    "os.environ[\"SQL_USER\"] = \"appuser\"\n",
+    "os.environ[\"SQL_PASSWORD\"] = \"changeme\"\n",
+    "os.environ[\"SQL_DATABASE\"] = \"appdb\"\n",
+    "os.environ[\"SQL_SSLMODE\"] = \"disable\"\n",
+    "from sqlalchemy import func\n",
+    "from sqlmodel import Field, SQLModel, select\n",
+    "\n",
+    "from sqlmodel_pg_kit import Repository, create_all, get_session\n",
+    "\n",
+    "\n",
+    "class Widget(SQLModel, table=True):\n",
+    "    id: Optional[int] = Field(default=None, primary_key=True)\n",
+    "    name: str\n",
+    "    in_stock: bool = True\n"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 2,
+   "id": "23860bb5",
+   "metadata": {},
+   "outputs": [
+    {
+     "name": "stdout",
+     "output_type": "stream",
+     "text": [
+      "Created: in_stock=True id=6 name='rocket'\n",
+      "Fetched by primary key: in_stock=True name='rocket' id=6\n",
+      "First page of in-stock widgets: [(9, 'probe'), (7, 'satellite')]\n",
+      "Search 'ro' -> [(9, 'probe'), (6, 'rocket')]\n",
+      "In-stock count: 3\n",
+      "Updated: in_stock=False id=6 name='rocket'\n",
+      "Deleted: True\n"
+     ]
+    }
+   ],
+   "source": [
+    "create_all()\n",
+    "repo = Repository(Widget)\n",
+    "\n",
+    "with get_session() as session:\n",
+    "    session.execute(Widget.__table__.delete())\n",
+    "    session.commit()\n",
+    "\n",
+    "    widget = repo.create(session, {\"name\": \"rocket\"})\n",
+    "    print(\"Created:\", widget)\n",
+    "\n",
+    "    repo.bulk_insert(\n",
+    "        session,\n",
+    "        [\n",
+    "            {\"name\": \"satellite\", \"in_stock\": True},\n",
+    "            {\"name\": \"capsule\", \"in_stock\": False},\n",
+    "            {\"name\": \"probe\", \"in_stock\": True},\n",
+    "        ],\n",
+    "    )\n",
+    "\n",
+    "    same = repo.get(session, widget.id)\n",
+    "    print(\"Fetched by primary key:\", same)\n",
+    "\n",
+    "    page = repo.list(\n",
+    "        session,\n",
+    "        where=Widget.in_stock.is_(True),\n",
+    "        order_by=[Widget.id.desc()],\n",
+    "        page=1,\n",
+    "        size=2,\n",
+    "    )\n",
+    "    print(\"First page of in-stock widgets:\", [(w.id, w.name) for w in page])\n",
+    "\n",
+    "    search_term = \"ro\"\n",
+    "    search_stmt = (\n",
+    "        select(Widget)\n",
+    "        .where(Widget.name.ilike(f\"%{search_term}%\"))\n",
+    "        .order_by(Widget.name.asc())\n",
+    "    )\n",
+    "    matches = session.exec(search_stmt).all()\n",
+    "    print(f\"Search '{search_term}' ->\", [(w.id, w.name) for w in matches])\n",
+    "\n",
+    "    count_stmt = select(func.count(Widget.id)).where(Widget.in_stock.is_(True))\n",
+    "    # scalar() keeps compatibility across SQLAlchemy versions\n",
+    "    inventory_count = session.exec(count_stmt).scalar() or 0\n",
+    "    print(\"In-stock count:\", inventory_count)\n",
+    "\n",
+    "    updated = repo.update(session, widget.id, in_stock=False)\n",
+    "    print(\"Updated:\", updated)\n",
+    "\n",
+    "    removed = repo.delete(session, widget.id)\n",
+    "    print(\"Deleted:\", removed)\n"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": null,
+   "id": "7637a17d",
+   "metadata": {},
+   "outputs": [],
+   "source": []
+  }
+ ],
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+  "kernelspec": {
+   "display_name": "sqlmodel",
+   "language": "python",
+   "name": "python3"
+  },
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+   "codemirror_mode": {
+    "name": "ipython",
+    "version": 3
+   },
+   "file_extension": ".py",
+   "mimetype": "text/x-python",
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+   "nbconvert_exporter": "python",
+   "pygments_lexer": "ipython3",
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+  }
+ },
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+ "nbformat_minor": 5
+}