默认hive一次执行一个stage,一个stage可以是一个mapreduce任务,也可以是一个抽样阶段,或者是一个合并阶段,还可以是一个limit阶段。 我们拿一个查询简单举个例子: -- 根据app_id和plan_id来查看收入 explain select app_id, plan_id, sum(pay_mnt) from ads.ads_grow_ad_material_statistic_df where date =...
[chararray] - scope-33 | | | |---Project[bytearray][4] - scope-32 | |---student: Load(hdfs://localhost:9000/pig_data/student_data.txt:PigStorage(',')) - scope19 2015-10-05 11:32:43,682 [main] INFO org.apache.pig.backend.hadoop.executionengine.mapReduceLayer.MRCompiler - ...
In this article I try to explain why Haskell keeps being such an important language by presenting some of its most distinguishing features and detailing them with working code examples.The presentation aims to be self-contained and does not require any previous knowledge of the language. I will ...
reduce the lexical variability in the behavioral repertoire, by using a task in which the set of actions is rewarded when executed in a fixed order, yet retaining variability in action timing (Murakami et al., 2014, 2017), a hallmark of self-initiated behavior (Killeen and Fetterman, 1988)...
原來用 map , filter 有名既。。。 January 18, 2022 用loop 就叫 imperative 用map 就叫 declarative 真係唔講唔知 最好就睇埋咩叫 how to write flat code有時我蠢 要人地解點解要整新功能 去解決緊咩問題 之 map/reduce in js for play with json/data December 23, 2021 https://rangle.io/...