Hadoop 在PIG中，是否可以通过定义列字段值来创建列字段

假设我有下面的结构化数据文件

1298712061228765236542123049824234209374 1203972012073042198531203948203498023498023 1203712012092329385612350924395798456892345 12348120121012234989230482034893204820398

在上面的文件中，前6位是（1-6）中的用户id，下8位是（7-12）中的年份日期，下6列是（13-18）中的计数字段，同样地，对于上面的平面文件，我有（19-30）中的产品id和（31-42）中的字符值列，所以我希望我的数据采用以下格式。我的意思是，我想用这个字段加载我的数据。在PIG或HIVE中是否有此选项

您能使用子字符串吗

A = LOAD 'DATA' USING PigStorage() AS (line); 
B = FOREACH A GENERATE SUBSTRING(line,1,6) AS UserID, SUBSTRING(line,7,12) AS Year_date ...

你会使用子字符串吗

A = LOAD 'DATA' USING PigStorage() AS (line); 
B = FOREACH A GENERATE SUBSTRING(line,1,6) AS UserID, SUBSTRING(line,7,12) AS Year_date ...

---

你可以在猪和蜂箱中使用它。以下是两种解决方案
清管器：

data = LOAD '/data.txt' USING PigStorage() AS (line);
strsplit = FOREACH data GENERATE 
SUBSTRING(line,1,6) AS UserID,
SUBSTRING(line,7,12) AS year_date,
SUBSTRING(line,13,18) AS Count,
SUBSTRING(line,19,30) AS product_id,
SUBSTRING(line,31,42) AS Character_values;  

当您转储时：
排土桩； （298712987129871）
（203972039720397203972039720397）
（203712037120371203712037120371）
（234812348123481234812348123481）

蜂巢：

data = LOAD '/data.txt' USING PigStorage() AS (line);
strsplit = FOREACH data GENERATE 
SUBSTRING(line,1,6) AS UserID,
SUBSTRING(line,7,12) AS year_date,
SUBSTRING(line,13,18) AS Count,
SUBSTRING(line,19,30) AS product_id,
SUBSTRING(line,31,42) AS Character_values;  

步骤1：创建临时表并加载原始数据

create table temp(line String)
ROW FORMAT DELIMITED
LINES TERMINATED BY '\n';
LOAD DATA INPATH '/data.txt' INTO TABLE temp;  

步骤2：创建一个适合您的数据的表格

   create table user(UserID String,year_date String,Count String,product_id String,Character_values String)
    ROW FORMAT DELIMITED
    FIELDS TERMINATED BY ','
    LINES TERMINATED BY '\n'; 

步骤3：将临时表插入actula表

INSERT INTO TABLE user
SELECT substr(line,0,6),substr(line,7,12),substr(line,13,18),substr(line,19,30),substr(line,31,42)FROM temp;

---

你可以在猪和蜂箱中使用它。以下是两种解决方案
清管器：

data = LOAD '/data.txt' USING PigStorage() AS (line);
strsplit = FOREACH data GENERATE 
SUBSTRING(line,1,6) AS UserID,
SUBSTRING(line,7,12) AS year_date,
SUBSTRING(line,13,18) AS Count,
SUBSTRING(line,19,30) AS product_id,
SUBSTRING(line,31,42) AS Character_values;  

当您转储时：
排土桩； （298712987129871）
（203972039720397203972039720397）
（203712037120371203712037120371）
（234812348123481234812348123481）

蜂巢：

data = LOAD '/data.txt' USING PigStorage() AS (line);
strsplit = FOREACH data GENERATE 
SUBSTRING(line,1,6) AS UserID,
SUBSTRING(line,7,12) AS year_date,
SUBSTRING(line,13,18) AS Count,
SUBSTRING(line,19,30) AS product_id,
SUBSTRING(line,31,42) AS Character_values;  

步骤1：创建临时表并加载原始数据

create table temp(line String)
ROW FORMAT DELIMITED
LINES TERMINATED BY '\n';
LOAD DATA INPATH '/data.txt' INTO TABLE temp;  

步骤2：创建一个适合您的数据的表格

   create table user(UserID String,year_date String,Count String,product_id String,Character_values String)
    ROW FORMAT DELIMITED
    FIELDS TERMINATED BY ','
    LINES TERMINATED BY '\n'; 

步骤3：将临时表插入actula表

INSERT INTO TABLE user
SELECT substr(line,0,6),substr(line,7,12),substr(line,13,18),substr(line,19,30),substr(line,31,42)FROM temp;