蜂巢：将列标题写入本地文件？

set hive.cli.print.header=true;

.hiverc

insert overwrite into [local] directory ...

0.7.1

set

dfs

!

create table new_table as
select 
  field1,
  field2,
  field3
from
(
  select
    0 as sort_col,  --header row gets lowest number
    \'field1_name\' as field1,
    \'field2_name\' as field2,
    \'field3_name\' as field3
  from
    some_small_table  --table needs at least 1 row
  limit 1  --only need 1 header row
  union all
  select
    1 as sort_col,  --original query goes here
    field1,
    field2,
    field3
  from
    main_table
) a
order by 
  sort_col  --make sure header row is first

create table test_dat
ROW FORMAT DELIMITED FIELDS TERMINATED BY \"\\t\" STORED AS 
INPUTFORMAT \"com.hadoop.mapred.DeprecatedLzoTextInputFormat\" 
OUTPUTFORMAT \"org.apache.hadoop.hive.ql.io.HiveIgnoreKeyTextOutputFormat\" 
LOCATION \'/tmp/test_dat\' as select * from YOUR_TABLE;

hive -e \'set hive.cli.print.header=true;select * from YOUR_TABLE limit 0\' > /tmp/test_dat/header.txt

cat header.txt 000* > all.dat

#!/usr/bin/env bash

# works like this:
# ./get_data.sh database.table > data.csv

INPUT=$1
TABLE=${INPUT##*.}
DB=${INPUT%.*}

HEADER=`hive -e \"
  set hive.cli.print.header=true;
  use $DB;
  INSERT OVERWRITE LOCAL DIRECTORY \'$TABLE\'
  row format delimited
  fields terminated  by \',\'
  SELECT * FROM $TABLE;\"`

HEADER_WITHOUT_TABLE_NAME=${HEADER//$TABLE./}
echo ${HEADER_WITHOUT_TABLE_NAME//[[:space:]]/,}
cat $TABLE/*