如何避免在节点中插入重复记录，sqlite [knex，objectionJS]

CREATE TABLE users (
  id INTEGER PRIMARY KEY AUTOINCREMENT,
  email TEXT UNIQUE NOT NULL
);

knex.schema.createTable('users', function (table) {
  table.increments('id').primary();
  table.string('email').unique().notNullable();
});

class User extends Model {
  static get tableName() {
    return 'users';
  }

  static get idColumn() {
    return 'id';
  }

  static get jsonSchema() {
    return {
      type: 'object',
      required: ['email'],
      properties: {
        id: { type: 'integer' },
        email: { type: 'string', format: 'email' }
      }
    };
  }
}

const user = { email: 'test@example.com' };

User.query()
  .insert(user)
  .catch(err => {
    if (err.message.includes('UNIQUE constraint failed')) {
      console.log('Duplicate record detected');
    } else {
      throw err;
    }
  });

knex('users')
  .insert(user)
  .onConflict('email')
  .merge();

User.query()
  .upsertGraphAndFetch(user);