Wechat applet 6 cloud development cloud database

Wechat applet 1- The basics of applets , Installation and use of development tools
Wechat applet 2-WXSS,WXS
Wechat applet 3- Applet lifecycle and components
Wechat applet 4- Applet api
Wechat applet 5- Real machine test

1. Development of cloud

    1). What is cloud development

Wechat cloud development is a professional applet development service launched by wechat team and Tencent cloud .
Developers can use cloud development to quickly develop small programs 、 Little games 、 The official account page, etc , And the original ability to open wechat .
Developers don't have to build servers , You can directly use the API Business development

    2). Advantages of cloud development

2. Using cloud development

    1). Create an applet , Choose cloud development

    2). Open Cloud Development , Create an environment

Each environment is isolated from each other , Have a unique environment ID, Contains independent database instances 、 Storage space 、 Cloud function configuration and other resources

3. Cloud database

Cloud development provides a JSON database , seeing the name of a thing one thinks of its function , Every record in the database is a JSON Formatted objects . A database can have multiple collections （ It's equivalent to a table in relational data ）, A collection can be seen as a JSON Array , Every object in the array is a record , The format of the record is JSON object

    1). Create a collection in the cloud database

Set up id Self increasing

Modify the permissions of the set , Give read and write permission , Otherwise, the permission exception will be reported ：database permission denied

    2). Cloud database - newly added

        (1). Insert data in the cloud console

Query the insert template on the cloud console

db.collection('user')
  .add({
    data: [
      {
        _id: '1',
        name: 'yw1',
        sex: ' male ',
        price: 10,
      },
      {
        _id: '2',
        name: 'yw2',
        sex: ' male ',
        price: 15,
      },
      {
        _id: '3',
        name: 'yw3',
        sex: ' Woman ',
        price: 20,
      },
    
    ]
  })

Execute insert statement

View set

        (2). Insert data through code

 add(){
    //  Get a reference to the cloud database 
    const db = wx.cloud.database()
 
    db.collection("user").add({
      data: {
         //id Auto increment is set , Can not pass , Will automatically give a value 
        // _id:"5",
        name: "yw5",
        age: 23,
        sex:" Woman ",
      }
    }).then(res=>{
      console.log(res)
      console.log(res._id)
    })
  }

    3). Cloud database - Inquire about

        (1). Query data through the cloud development console

db.collection('user')
  .where({
    name: 'yw1'
  })
  .field({
    name: true,
    age: true,
  })
  .get()

        (2). Query data through code

//  Get a reference to the cloud database 
    const db = wx.cloud.database()
    db.collection('user').where({
        name: 'yw1',
    }).get({
      success: function(res) {
      console.log(res)
     }
    })
  }

    4). Cloud database - Delete

        (1). Delete through the cloud development console

doc It's filled in with id

db.collection('user').doc('1')
  .remove()

        (2). Delete by code

  //  Get a reference to the cloud database 
    const db = wx.cloud.database()
    db.collection('user').where({
        name: 'yw2',
    }).remove()

    5). Cloud database - to update

        (1). Update through the cloud development console

db.collection('user')
  .where({
    name: 'yw3'
  })
  .update({
    data: {
      age:56,
      sex:' male '
    }
  })

        (2). Modify... By code

  const db = wx.cloud.database()
    db.collection('user').where({
        name: 'yw3',
    }).update({
      data: {
        age:58,
        sex:' male '
      }
    }).then(res=>{
      console.log(res)
      console.log(res._id)
    })