salix/services/loopback/common/models/user.json

{
  "name": "user",
  "base": "User",
  "options": {
    "mysql": {
      "table": "salix.user"
    }
  },
  "properties": {
    "id": {
      "id": true,
      "type": "Number",
      "forceId": false
    },
    "username":{
      "type": "string"
    }
  }
}