sqoop操作之ORACLE导入到HIVE

导入表的所有字段

sqoop import --connect jdbc:oracle:thin:@192.168.1.107:1521:ORCL 
--username SCOTT --password tiger 
--table EMP 
--hive-import  --create-hive-table --hive-table emp  -m 1;

如果报类似的错:

ERROR tool.ImportTool: Encountered IOException running import job: org.apache.hadoop.mapred.FileAlreadyExistsException: Output directory EMP already exists

先去HDFS系统中删除该文件: hadoop fs -rmr /user/hadoop/EMP

如果报类似的错:

FAILED: Error in metadata: AlreadyExistsException(message:Table emp already exists)

如果报类似的错:

hive.HiveImport: Exception in thread "main" java.lang.NoSuchMethodError: org.apache.thrift.EncodingUtils.setBit(BIZ)B

这是因为在同路径下安装了hive和hbase,而hbase和hive的lib目录下的thrift版本不同。
hbase下的为libthrift-0.x.0.jar,hive下的为libthrift-0.x.0.jar。将Hbase下的0.x.0版的删除,换为0.x.0的即可。
ps:不知为什么Sqoop向Hive中导入数据还有Hbase的事

说明:hive表已经存在,需要先删除

查看:

desc emp;
empno   double
ename   string
job     string
mgr     double
hiredate        string
sal     double
comm    double
deptno  double

select * from emp; 7369.0 SMITH CLERK 7902.0 1980-12-17 00:00:00.0 800.0 NULL 20.0 7499.0 ALLEN SALESMAN 7698.0 1981-02-20 00:00:00.0 1600.0 300.0 30.0 7521.0 WARD SALESMAN 7698.0 1981-02-22 00:00:00.0 1250.0 500.0 30.0 7566.0 JONES MANAGER 7839.0 1981-04-02 00:00:00.0 2975.0 NULL 20.0 7654.0 MARTIN SALESMAN 7698.0 1981-09-28 00:00:00.0 1250.0 1400.0 30.0 ……

注:一般情况下不使用--create-hive-table去创建表的,因为它创建的表的字段格式,不符合我们的要求。

导入表的指定字段

手工创建hive表:

create table emp_column(
empno int,
ename string,
job string,
mgr int,
hiredate string,
sal double,
comm double,
deptno int
)
row format delimited fields terminated by '	' lines terminated by '
' 
stored as textfile;
sqoop import --connect jdbc:oracle:thin:@192.168.1.107:1521:ORCL 
--username SCOTT --password tiger 
--table EMP --columns "EMPNO,ENAME,JOB,SAL,COMM" 
--fields-terminated-by '	' --lines-terminated-by '
' 
--hive-drop-import-delims --hive-import  --hive-table emp_column 
-m 3;

说明:重新再执行,每重复导入一次,hive中的数据会重复导入。

sqoop import --connect jdbc:oracle:thin:@192.168.1.107:1521:ORCL 
--username SCOTT --password tiger 
--table EMP --columns "EMPNO,ENAME,JOB,SAL,COMM" 
--fields-terminated-by '	' --lines-terminated-by '
' 
--hive-drop-import-delims --hive-overwrite --hive-import --hive-table emp_column 
-m 3;

注:--hive-overwrite指定覆盖表里已经存在的记录,99%都是要使用overwrite的,避免重跑时产生重复数据。

导入表的指定字段到hive分区表

创建hive分区表:

create table emp_partition(
empno int,
ename string,
job string,
mgr int,
hiredate string,
sal double,
comm double,
deptno int
)
partitioned by (pt string)
row format delimited fields terminated by '	' lines terminated by '
' 
stored as textfile;

导入pt='2013-08-01'

sqoop import --connect jdbc:oracle:thin:@192.168.1.107:1521:ORCL 
--username SCOTT --password tiger 
--table EMP --columns "EMPNO,ENAME,JOB,SAL,COMM" 
--hive-overwrite --hive-import  --hive-table emp_partition 
--fields-terminated-by '	' --lines-terminated-by '
' 
--hive-drop-import-delims --hive-partition-key 'pt' --hive-partition-value '2013-08-01' 
-m 3;

导入pt='2013-08-02'

sqoop import --connect jdbc:oracle:thin:@192.168.1.107:1521:ORCL 
--username SCOTT --password tiger 
--table EMP --columns "EMPNO,ENAME,JOB,SAL,COMM" 
--hive-overwrite --hive-import  --hive-table emp_partition 
--fields-terminated-by '	' --lines-terminated-by '
' 
--hive-drop-import-delims  --hive-partition-key 'pt' --hive-partition-value '2013-08-02' 
-m 3;

查询:

select * from emp_partition where pt='2013-08-01';
select * from emp_partition where pt='2013-08-02';