Hive split函数获取元素数

Question

我想知道Hive是否可以选择从字符串中获取元素数量，例如david.Udert。我试过这个split(type,'\\.')[2][3]
这split(type,'\\.')[2:3]而且它不起作用， 有没有选择做这样的事情来把两个单词放在一起？

Answer 1

• 数组索引以0

  开头

  with t as (select 'Now.I.heard.you.know.that.secret.chord' as mycol)
  
  select  split(t.mycol,'\\.')    as arr
     ,split(t.mycol,'\\.')[0] as arr_1st_element
     ,split(t.mycol,'\\.')[1] as arr_2nd_element
     ,split(t.mycol,'\\.')[2] as arr_3nd_element
  
  from    t
  ;
  

  +----------------------------------------------------------+-----------------+-----------------+-----------------+
  |                           arr                            | arr_1st_element | arr_2nd_element | arr_3nd_element |
  +----------------------------------------------------------+-----------------+-----------------+-----------------+
  | ["Now","I","heard","you","know","that","secret","chord"] | Now             | I               | heard           |
  +----------------------------------------------------------+-----------------+-----------------+-----------------+
  

• 至少目前不支持数组切片。如果要切片，请在拆分

  之前进行切片

  with t as (select 'Now.I.heard.you.know.that.secret.chord' as mycol)
  
  select  split(substring_index(substring_index(t.mycol,'.',7),'.',-3),'\\.')     as slice_option_1
     ,split(regexp_extract(t.mycol,'(.*?\\.){4}((\\.?[^.]*){0,3})',2),'\\.')  as slice_option_2
  
  from    t
  ;
  

  +--------------------------+--------------------------+
  |      slice_option_1      |      slice_option_2      |
  +--------------------------+--------------------------+
  | ["know","that","secret"] | ["know","that","secret"] |
  +--------------------------+--------------------------+