Hive数据仓库行转列

查了很多资料发现网上很多文章都是转发和抄袭,有些问题。这里分享一个自己项目中使用的行转列例子,供大家参考。代码如下:

sql 复制代码
SELECT
  my_id,
  nm_cd_map['A'] AS my_cd_a,
  nm_cd_map['B'] AS my_cd_b,
  nm_cd_map['C'] AS my_cd_c,
  nm_num_map['A'] AS my_num_a,
  nm_num_map['B'] AS my_num_b,
  nm_num_map['C'] AS my_num_c
FROM
  (
    SELECT
      t.my_id,
      STR_TO_MAP(my_nm_cds,';',':') AS nm_cd_map,
      STR_TO_MAP(my_nm_nums,';',':') AS nm_num_map
    FROM
      (
        SELECT
          my_id,
          CONCAT_WS(';',COLLECT_LIST(CONCAT(my_nm,':',my_cd))) AS my_nm_cds,
          CONCAT_WS(';',COLLECT_LIST(CONCAT(my_nm,':',my_num))) AS my_nm_nums
        FROM
          (
            SELECT '1' AS my_id,'A' AS my_nm,'D01' AS my_cd,19 AS my_num
            UNION ALL
            SELECT '1' AS my_id,'B' AS my_nm,'D04' AS my_cd,18 AS my_num
            UNION ALL
            SELECT '1' AS my_id,'C' AS my_nm,'D02' AS my_cd,17 AS my_num
            UNION ALL
            SELECT '2' AS my_id,'A' AS my_nm,'D03' AS my_cd,16 AS my_num
            UNION ALL
            SELECT '2' AS my_id,'B' AS my_nm,'D05' AS my_cd,15 AS my_num
            UNION ALL
            SELECT '2' AS my_id,'C' AS my_nm,'D06' AS my_cd,14 AS my_num
          )
        GROUP BY my_id
      ) t
  ) t
WHERE 1=1;

如果是在SparkSQL或Presto平台,或者阿里云的MaxCompute平台,还可使用如下方式:

sql 复制代码
-- 其实也可使用CONCAT然后STR_TO_MAP的方式,或者用MAP_FROM_ARRAYS,再或者用数组排序后ARRAY[n] AS的方式
SELECT
  my_id,
  nm_cd_map['A'] AS my_cd_a,
  nm_cd_map['B'] AS my_cd_b,
  nm_cd_map['C'] AS my_cd_c,
  nm_num_map['A'] AS my_num_a,
  nm_num_map['B'] AS my_num_b,
  nm_num_map['C'] AS my_num_c
FROM
  (
    SELECT
      t.my_id,
      MAP_FROM_ENTRIES(COLLECT_LIST(nm_cd)) AS nm_cd_map,
      MAP_FROM_ENTRIES(COLLECT_LIST(nm_num)) AS nm_num_map
    FROM
      (
        SELECT
          my_id,
          my_nm,
          my_cd,
          my_num,
          STRUCT(my_nm,my_cd) AS nm_cd,
          STRUCT(my_nm,my_num) AS nm_num
        FROM
          (
            SELECT '1' AS my_id,'A' AS my_nm,'D01' AS my_cd,19 AS my_num
            UNION ALL
            SELECT '1' AS my_id,'B' AS my_nm,'D04' AS my_cd,18 AS my_num
            UNION ALL
            SELECT '1' AS my_id,'C' AS my_nm,'D02' AS my_cd,17 AS my_num
            UNION ALL
            SELECT '2' AS my_id,'A' AS my_nm,'D03' AS my_cd,16 AS my_num
            UNION ALL
            SELECT '2' AS my_id,'B' AS my_nm,'D05' AS my_cd,15 AS my_num
            UNION ALL
            SELECT '2' AS my_id,'C' AS my_nm,'D06' AS my_cd,14 AS my_num
          )
      ) t
    GROUP BY my_id
  ) t
WHERE 1=1;
相关推荐
王小王-1234 小时前
基于Hadoop的餐饮大数据分析系统的设计与实现
hive·hadoop·flask·sqoop·pyecharts·hadoop餐饮大数据分析·hadoop美食数据分析
張萠飛10 天前
hive集群优化和治理常见的问题答案
数据仓库·hive·hadoop
fpcc12 天前
c++26新功能—hive容器
c++·hive
liuze40814 天前
在VMware虚拟机集群中,完成Hive的安装部署
数据仓库·hive·hadoop
雷神乐乐14 天前
Hive优化详细讲解
数据仓库·hive·hadoop
Edingbrugh.南空14 天前
Hudi 与 Hive 集成
数据仓库·hive·hadoop
Edingbrugh.南空15 天前
Hive集成Paimon
数据仓库·hive·hadoop
雷神乐乐15 天前
Hive的分区表(静态分区、动态分区)、分桶表、四种排序方式和数据加载方式
数据仓库·hive·hadoop
Edingbrugh.南空16 天前
SeaTunnel与Hive集成
数据仓库·hive·hadoop
Edingbrugh.南空17 天前
Apache Iceberg与Hive集成:非分区表篇
hive·hadoop·apache