Question

我一直致力于使用PostgreSQL数据库的NodeJS项目。我正在尝试实现迁移到数据库。另外，使用Sequelize。设置迁移文件夹和配置后，它会在运行db：migrate

时抛出错误

错误是： “从v4.0.0开始，需要明确提供方言”

Answer 1

我的解决方案基于我为NODE_ENV变量设置的内容。

echo $NODE_ENV

如果您没有为该变量设置任何内容，请尝试使用以下内容进行设置：

export NODE_ENV=development

如果值存在，请确保您的配置文件中有值的条目。对我来说，我喜欢使用local。所以我不得不将我的配置更新为：

{
 local: {
  username: 'root',
  password: null,
  database: 'database_dev',
  host: '127.0.0.1',
  dialect: 'postgres'
  },
 development: {
  username: 'root',
  password: null,
  database: 'database_dev',
  host: '127.0.0.1',
  dialect: 'postgres'
  },
  test: {
  username: 'root',
  password: null,
  database: 'database_test',
  host: '127.0.0.1',
  dialect: 'postgres'
 },
 production: {
  username: 'root',
  password: null,
  database: 'database',
  host: '127.0.0.1',
  dialect: 'postgres'
 }
}

Answer 2

检查一次方言。

const Sequelize = require('sequelize'); // Option 1: Passing parameters separately const sequelize = new Sequelize('database', 'username', 'password', { host: 'localhost', dialect: /* one of 'mysql' | 'mariadb' | 'postgres' | 'mssql' */ });

Answer 3

您是否忘记将方言添加到配置中？见：http://docs.sequelizejs.com/manual/tutorial/migrations.html

Answer 4

检查配置文件（env名称）

＆＃13;

{
  development: {
    username: 'root',
    password: null,
    database: 'database_development',
    host: '127.0.0.1',
    dialect: 'mysql'
  },
  test: {
    username: 'root',
    password: null,
    database: 'database_test',
    host: '127.0.0.1',
    dialect: 'mysql'
  },
  production: {
    username: 'root',
    password: null,
    database: 'database_production',
    host: '127.0.0.1',
    dialect: 'mysql'
  }
}

＆＃13;

Answer 5

如果您在运行npm server

之前未设置任何.env变量

您可能会收到该错误。因此每次重新启动应用程序以进行更改。你将不得不再次出口

export DATABASE_URL=<your-db-url>

Answer 6

我遇到了同样的错误，并且在代码中看到了这个错误。

  title: {
    type: Sequelize,
    allowNull: false,
  },

以此更改我的代码，问题得以解决：

  title: {
    type: Sequelize.STRING,
    allowNull: false,
  },

Answer 7

我的问题是我没有正确指向配置文件。它说“已成功加载”，但我没有指向正确的文件。

它应该显示为“已加载的配置文件“ [某些路径] /config.js”。”

Answer 8

如果模型架构中存在错误，也可能导致此错误。

我有：

middle_name: {
    type: Sequelize.Sequelize,
    allowNull: false,
}

应该是哪个：

middle_name: {
    type: Sequelize.STRING,
    allowNull: false,
}

Answer 9

就我而言，我将config.js声明为：

module.exports = {
  production: {
    database: process.env.DB_PROD_DATABASE,
    username: process.env.DB_PROD_USERNAME,
    password: process.env.DB_PROD_PASSWORD,
    options: {
      host: process.env.DB_PROD_HOST,
      port: process.env.DB_PROD_PORT,
      dialect: 'postgres',
      define: {
        paranoid: true,
        timestamp: true,
        freezeTableName: true,
        underscored: false
      }
    }
  },
  development: {
    database: process.env.DB_DEV_DATABASE || 'database_name',
    username: process.env.DB_DEV_USERNAME || 'user_name', 
    password: process.env.DB_DEV_PASSWORD || 'pass', 
    host: process.env.DB_DEV_HOST || 'localhost',
    port: process.env.DB_DEV_PORT || 5432,
    dialect: 'postgres',
    define: {
      paranoid: true,
      timestamp: true,
      freezeTableName: true,
      underscored: false
    }
  }
}

但是应该像这样：

module.exports = {
  production: {
    database: process.env.DB_PROD_DATABASE,
    username: process.env.DB_PROD_USERNAME,
    password: process.env.DB_PROD_PASSWORD,
    options: {
      host: process.env.DB_PROD_HOST,
      port: process.env.DB_PROD_PORT,
      dialect: 'postgres',
      define: {
        paranoid: true,
        timestamp: true,
        freezeTableName: true,
        underscored: false
      }
    }
  },
  development: {
    database: 'database_name',
    username: 'user_name', 
    password: 'pass', 
    host: 'localhost',
    port: 5432,
    dialect: 'postgres',
    define: {
      paranoid: true,
      timestamp: true,
      freezeTableName: true,
      underscored: false
    }
  }
}

没有process.env.DB_DEV_DATABASE || 'database_name'例如

Answer 10

我认为您在项目中遗漏了 .env 文件

Answer 11

如果您遇到此错误，则必须在 password_for_rootUser 之后以对象形式添加其他参数，并需要根据您的 RDBMS 指定这些属性

var Sequilize=require('sequelize');
var connection =new Sequilize('db_name','root_user_name','password_for_rootUser',{
    host:'localhost',
    dialect:'mysql'|'mariadb'|'sqlite'|'postgress'|'mssql',
    pool:{
        max:5,
        min:0,
        idle:10000
    },
//for sqlite only
storage:path/to/database.sqlite


});


var Article=connection.define('tableName',{
    title:Sequilize.STRING, // your cloumn name with data type
    body:Sequilize.TEXT    // your cloumn name with data type
});

connection.sync();

希望这能解决您的问题

Answer 12

就我而言，问题是我从 config.ts 导出配置的方式 export const = {} 无效
但 module.exports 有效：

module.exports = {
  development: {
    dialect: process.env.DB_DIALECT,
    username: process.env.DB_USER,
    password: process.env.DB_PASS,
    database: process.env.DB_NAME_DEVELOPMENT,
    host: process.env.DB_HOST,
    port: process.env.DB_PORT,
  },
  test: {
    dialect: process.env.DB_DIALECT,
    username: process.env.DB_USER,
    password: process.env.DB_PASS,
    database: process.env.DB_NAME_DEVELOPMENT,
    host: process.env.DB_HOST,
    port: process.env.DB_PORT,
  },
  production: {
    dialect: process.env.DB_DIALECT,
    username: process.env.DB_USER,
    password: process.env.DB_PASS,
    database: process.env.DB_NAME_DEVELOPMENT,
    host: process.env.DB_HOST,
    port: process.env.DB_PORT,
  },
};

从v4.0.0开始，需要明确提供方言

12 个答案: