add range condition

[XueSeason]

定制 where 查询条件时，研究了下源代码，发现仅支持 = 和 IN 操作，本人项目开发到一半，发现不能满足需求，故扩展了 where 对象的能力，更加灵活可控。

[fengmk2]

date: { op: '>=', value: '20170504'}

这样会更好吧，可以参考一下业务关于 where 的 api 实现。

[fengmk2]

@dead-horse @coolme200 对于 api 有什么好建议吗？

[dead-horse]

这里用数组的考虑是什么？

[dead-horse]

date >= 100 AND date <= 200 这种需求么？

[XueSeason]

对，就是这个需求。

[dead-horse]

最好也支持只传一个 object 的场景吧 date: { op: '>=', value: '20170504'}

[codecov-io]

Codecov Report

❗ No coverage uploaded for pull request base (master@7cb4e75). Click here to learn what that means.
The diff coverage is 60%.

@@            Coverage Diff            @@
##             master      #24   +/-   ##
=========================================
  Coverage          ?   97.53%           
=========================================
  Files             ?        6           
  Lines             ?      284           
  Branches          ?       41           
=========================================
  Hits              ?      277           
  Misses            ?        7           
  Partials          ?        0

Impacted Files	Coverage Δ
lib/operator.js	97.36% <60%> (ø)

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[fengmk2]

OR 的功能估计也需要考虑一下 eggjs/egg#1035

[musicode]

几个月过去了，这个 PR 还有下文吗

[wulv]

这个PR还有下文吗？

[xyeric]

还有LIKE的场景，能不能支持~ @fengmk2

where: {
  key: `LIKE %${keyword}%`
}

[shiny]

Any updates?

[Benny233]

哟，or会有吗？需要的老哥们，咱们组队贡献代码吧！？