从数据库中选择特定字段 [英] Select specific fields from database

问题描述

我只是想知道是否可以使用水线选择特定字段，下面给出了orientdb查询.

I just want to know that is it possible to select specific fields using waterline, orientdb query is given below.

e.g. 
select phone from user

我想使用此查询从用户顶点中选择手机

I want to select phone from user vertices by using this query

userModel.find(phone)
.then(function(phonelist){ 
  if(!phonelist) 
     console.log('msg: RECORD_NOT_FOUND'); 
  else 
     console.log(phonelist);
.catch(function(err){ console.log('err: 'err'); });

推荐答案

是的，这是可能的，例如，您只需要将 select 添加到您的搜索条件中(假设您正在搜索记录id 为 1):

Yes, it's possible, you just need to add select to your search criteria, for example (assuming you are searching for a records with id 1):

userModel.find({ select: ['phone'], id: 1 })

或者:

userModel.find({ select: ['phone'], where: { id: 1 } })

或者如果您想要所有记录，则无需提供条件:

or if you want all records, you don't need to supply criteria:

userModel.find({ select: ['phone'] })

这似乎没有记录在任何地方，但它应该.在 0.11 版本中，还可以通过执行 model.pick('name', 'age') 来定义选择:https://github.com/balderdashy/waterline/pull/952

This doesn't seem to be documented anywhere but it should. In version 0.11 it will also possible to define select by doing model.pick('name', 'age'): https://github.com/balderdashy/waterline/pull/952

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