如何在 Hive 中按原始顺序选择行? [英] How to select the rows in original order in Hive?

问题描述

我想从 mytable 中选择具有确定数字的原始行中的行.众所周知，关键字limit"会随机选择行.mytable 中的行是有序的.我只想按原始顺序选择它们.例如，选择 10000 行，这意味着从第 1 行到第 10000 行.如何实现这一点?谢谢.

I want to select rows from mytable in original rows with definite numbers. As we know, the key word 'limit' will randomly select rows. The rows in mytable are in order. I just want to select them in their original order. For example, to select the 10000 rows which means from row 1 to row 10000. How to realize this? Thanks.

推荐答案

尝试:

SET mapred.reduce.tasks = 1
SELECT * FROM ( 
    SELECT *, ROW_NUMBER() OVER () AS row_num
    FROM table ) table1 
SORT BY row_num LIMIT 10000

这篇关于如何在 Hive 中按原始顺序选择行?的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！