nullsfirstlast索引

nulls first & nulls last 对索引影响

-- 当我们需要排序字段时，比如order by name,如果name字段定义时没有not null时，就有可能涉及到null值的排序 -- 如果不注意，可能会造成隐藏的bug，pg默认null是无穷大，在升序时排在最后面，当然在排序时也可以指定 nulls first 或 nulls last -- 具体使用方法在此不在复述，本文主要是讲的是在创建索引时指定 nulls first 或 nu...

nulls first & nulls last 对索引影响

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云数据库 HBase 版

云数据库HBase是面向大数据领域的一站式NoSQL服务，100%兼容开源HBase并深度扩展，支持海量数据下的实时存储、高并发吞吐、轻SQL分析等，是风控、推荐、广告、物联网、车联网、Feeds流、数据大屏等场景首选数据库。

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