sequelize with postgres database not working after migration from mysql

问题

I change MySQL databese into postgreSQL in sequelize. But After migration I have issue with upper and lowercase first letter in Table or Model... Before my MySQL version was working properly but after migration I got error message: 500 SequelizeDatabaseError: relation "Users" does not exist

My User model:

module.exports = function(sequelize, Sequelize) {
  var User = sequelize.define("User", {
    // profile
    userlevel: Sequelize.STRING,
    restaurant: Sequelize.STRING,
    access: Sequelize.STRING,
    optionsid: Sequelize.STRING,
    email: Sequelize.STRING,
    name: Sequelize.STRING,
    gender: Sequelize.STRING,
    location: Sequelize.STRING,
    website: Sequelize.STRING,
    picture: Sequelize.STRING,
    // Oauth
    password: {
      type: Sequelize.STRING,
      set: function(v) {
        var salt = bcrypt.genSaltSync(5);
        var password = bcrypt.hashSync(v, salt);
        return this.setDataValue('password', password);
      }
    },
    .....

Migration file:

"use strict";
module.exports = {
  up: function(migration, DataTypes, done) {
    migration.createTable("users", {
      id: {
        allowNull: false,
        autoIncrement: true,
        primaryKey: true,
        type: DataTypes.INTEGER
      },
      userlevel: {
        type: DataTypes.STRING,
        defaultValue: '5'
      },
      restaurant: {
        type: DataTypes.STRING,
        defaultValue: ''
      },
      access: {
        type: DataTypes.STRING,
        defaultValue: '1'
      },
      optionsid: {
        type: DataTypes.STRING,
        defaultValue: ''
      },
      email: {
        type: DataTypes.STRING,
        allowNull: false
      },
      name: {
        type: DataTypes.STRING,
        defaultValue: ''
      },
      gender: {
        type: DataTypes.STRING,
        defaultValue: ''
      },
      location: {
        type: DataTypes.STRING,
        defaultValue: ''
      },
      website: {
        type: DataTypes.STRING,
        defaultValue: ''
      },
      picture: {
        type: DataTypes.STRING,
        defaultValue: ''
      },
      password: {
        type: DataTypes.STRING
      },
      facebook: {
        type: DataTypes.STRING
      },
      twitter: {
        type: DataTypes.STRING
      },
      google: {
        type: DataTypes.STRING
      },
      tokens: {
        type: DataTypes.STRING
      },
      resetPasswordToken: {
        type: DataTypes.STRING
      },
      resetPasswordExpires: {
        type: DataTypes.DATE
      },
      createdAt: {
        allowNull: false,
        type: DataTypes.DATE
      },
      updatedAt: {
        allowNull: false,
        type: DataTypes.DATE
      }
    }).done(done);
  },
  down: function(migration, DataTypes, done) {
    migration.dropTable("users").done(done);
  }
};

If I change first letter of table in postgreSQL to uppercase everything is working properly...

回答1:

PostgreSQL folds the names of ordinary identifiers to lower case. So users, Users, and USERS all resolve to the identifier users.

Delimited identifiers are different. (Delimited identifiers are surrounded by double quotes.) The identifiers "users", "Users", and "USERS" are three different identifiers.

Your migration created the table "users". Sequelize is looking for the table "Users". (Delimited identifiers--two different tables.)

You should probably change the identifier in your migration to "Users". There are other ways, but this is the path of least resistance. If this is already in production, you might be better off writing another migration that renames "users" to "Users".

来源：https://stackoverflow.com/questions/28844617/sequelize-with-postgres-database-not-working-after-migration-from-mysql