使用pouchdb做简单的本地数据库增删改查，浏览器端和nodejs端都适用

浏览器端增删改查

<!DOCTYPE html>
<html lang="en">

<head>
  <meta charset="UTF-8">
  <meta http-equiv="X-UA-Compatible" content="IE=edge">
  <meta name="viewport" content="width=device-width, initial-scale=1.0">
  <title>pouchdb</title>
  <script src="https://libs.baidu.com/jquery/1.10.2/jquery.min.js"></script>
  <script src="https://unpkg.com/pouchdb@8.0.1/dist/pouchdb.js"></script>
  <script src="https://unpkg.com/pouchdb@8.0.1/dist/pouchdb.find.js"></script>
  <style>
    th {
      width: 200px;
    }
    td {
      text-align: center;
    }
  </style>
</head>

<body>
  <button onclick="查询()">查询</button>
  <br><br>
  _id<input type="text" id="_id" />
  <br>
  a<input type="text" id="a" />
  b<input type="text" id="b" />
  <br><br>
  <button onclick="新增数据()">新增数据</button>
  <button onclick="修改数据()">修改数据</button>
  <button onclick="删除数据()">删除数据</button>
  <br><br>
  <table id="example-table" border="1">
    <thead>
      <tr>
        <th>_id</th>
        <th>a</th>
        <th>b</th>
      </tr>
    </thead>
    <tbody>
    </tbody>
  </table>
  <script>
    var db = new PouchDB('my_db');

    async function 查询() {
      //查
      const data = await db.find({
        selector: {},
        sort: [
          { '_id': 'asc' },//asc 升序 desc 降序
        ],
        fields: ['id', 'a', 'b'],//'_id', '_rev', 
      })
      console.log('查询', data.docs)
      const tableBody = document.getElementById('example-table').getElementsByTagName('tbody')[0];
      // 清空表格
      tableBody.innerHTML = '';

      // 循环遍历数组对象，创建表格的行和单元格
      for (let i = 0; i < data.docs.length; i++) {
        const row = tableBody.insertRow(i);
        const idCell = row.insertCell(0);
        const aCell = row.insertCell(1);
        const bCell = row.insertCell(2);

        idCell.innerHTML = data.docs[i].id;
        aCell.innerHTML = data.docs[i].a;
        bCell.innerHTML = data.docs[i].b;
      }
      $('#_id').val('')
      $('#a').val('')
      $('#b').val('')
    }

    async function 新增数据() {
      const a = $('#a').val()
      const b = $('#b').val()
      await db.put({
        _id: String(Date.now()),
        id: Date.now(),
        a,
        b,
      })
      console.log('新增数据成功')
      查询()
    }

    async function 修改数据() {
      const _id = $('#_id').val()
      const a = $('#a').val()
      const b = $('#b').val()
      if (!_id) {
        console.log('请填写_id')
        return
      }
      const doc = await db.get(_id)
      // console.log(doc)
      await db.put({
        ...doc,
        a,
        b,
      })
      console.log('修改数据成功')
      查询()
    }

    async function 删除数据() {
      const _id = $('#_id').val()
      if (!_id) {
        console.log('请填写_id')
        return
      }
      const doc = await db.get(_id)
      await db.remove(doc)
      console.log('删除数据成功')
      查询()
    }

    查询()

  </script>
</body>

</html>

nodejs端增删改查，这不就基本脱离数据库了吗

const PouchDB = require('pouchdb');
PouchDB.plugin(require('pouchdb-find'))

var db = new PouchDB('database/my_db');

async function init() {
  //增
  // await db.put({
  //   _id: String(Date.now()),
  //   id: Date.now(),
  //   title: '11111',
  //   author: '2222'
  // })

  //查
  const list = await db.allDocs({
    include_docs: true,
    descending: true,
    selector: {
      // title: '111',
    },
  })

  //查
  const data = await db.find({
    descending: false,
    selector: {
      // title: '111',
    },
    sort: [
      { _id: 'desc' },
    ],
    fields: ['_id', '_rev', 'id', 'title', 'author'],
  })

  // db.put({
  //   _id: '2',
  //   title: '111',
  //   author: '222'
  // }).then(function () {
  //   console.log('Document inserted!');
  // }).catch(function (error) {
  //   console.error(error);
  // });

  db.remove('1681982410780', '1-fc1d15d67959343816f9601686048f3b')

  // const res = await db.get('2')
  // console.log(list.rows)
  console.log(data)

  //清空数据库
  // await db.destroy()

  //删除数据

}

init()