Question

首先，这是关于MySQL的表格

+-----------+-------------+------+-----+---------+----------------+
| Field     | Type        | Null | Key | Default | Extra          |
+-----------+-------------+------+-----+---------+----------------+
| MemberID  | int(11)     | NO   | PRI | NULL    | auto_increment |
| FirstName | varchar(50) | NO   |     | NULL    |                |
| LastName  | varchar(50) | NO   |     | NULL    |                |
| CityID    | int(11)     | NO   | MUL | NULL    |                |
+-----------+-------------+------+-----+---------+----------------+

我使用Sequelize创建了从Node JS服务器到MySQL的连接，如下所示：

var db = new Sequelize(
  'member','root', null,
  {
    host    : 'localhost',
    port    :  3306,
    dialect : 'mysql'
  }
);

然后我使用Sequelize在我的Node JS服务器上定义了MySQL表格，如下所示：

var memberlist = db.define('members', {
    MemberID  : Sequelize.INTEGER,
    FirstName : Sequelize.STRING,
    LastName  : Sequelize.STRING
});

然后我创建了一个GraphQL Schema来获取数据以及模式的相应解析器

 var schema = buildSchema(`

    type Members {
      MemberID: ID!
      FirstName: String!
      LastName: String!
      CityID: City!
    }

    type City {
      CityID: ID!
      CityName: String!
    }

    type Query {
      allMembers: [Members]!
    }
`);

 var root = {

    allMembers  : function(){
       memberlist.find({}).complete(function (err,data) 
       {}).then(({data}) => data)},

 }

var app = express();
 app.use('/graphql', graphqlHTTP({
    schema: schema,
    rootValue: root,
    graphiql: true
}));

当我尝试在GraphQL上运行查询时，出现以下错误：

Executing (default): SELECT `id`, `MemberID`, `FirstName`, `LastName`, 
`createdAt`, `updatedAt` FROM `members` AS `members` LIMIT 1;

Unhandled rejection SequelizeDatabaseError: Unknown column 'id' in 'field 
list'

id（和createdAt，updateAt）字段来自哪里，因为我没有在Sequelize上定义它们？

Answer 1

我在这里假设，如果你没有明确告诉sequelize主键在你的模型中是什么，它将假设它是一个名为id的字段

尝试以下方法告诉你的主键是什么;

const memberlist = db.define('members', {
  MemberID  : {
    type: DataTypes.INTEGER,
    primaryKey: true,
  }
  FirstName : Sequelize.STRING,
  LastName  : Sequelize.STRING
});

为您自动添加createdAt和updatedAt字段。要停止发生这种情况，请使用

const memberlist = db.define('members', {
  MemberID  : {
    type: DataTypes.INTEGER,
    primaryKey: true,
  }
  FirstName : Sequelize.STRING,
  LastName  : Sequelize.STRING
}, {
  timestamps: false
});

使用Sequelize从MySQL获取数据到GraphQL失败

1 个答案: