Data Manipulation Language：資料操縱語言

資料匯入

1、load模式

LOAD DATA [LOCAL] INPATH 'filepath' [OVERWRITE] INTO TABLE tablename [PARTITION(partcol1=val1,partcol2=val2 ...)]

• load data:表示載入資料
• local:表示從本地載入資料到 hive 表；否則從 HDFS 載入資料到hive 表
• inpath:表示載入資料的路徑
• overwrite:表示覆蓋表中已有資料，否則表示繼續新增資料
• into table tablename:表示要載入資料到哪個表
• partition:表示上傳到指定分割槽

hive (bigdata)> create table student(id int,name string)
              > row format delimited fields terminated by '\t';
OK
Time taken: 1.404 seconds
hive (bigdata)> load data local inpath '/opt/test/student' into table student;
Loading data to table bigdata.student
OK
Time taken: 2.4 seconds
 

2、insert模式

INSERT OVERWRITE TABLE tablename1 [PARTITIO
N (partcol1=val1, partcol2=val2 ...) [IF NO
T EXISTS]] select_statement1 FROM from_stat
ement;
INSERT INTO TABLE tablename2 [PARTITION (pa
rtcol1=val1, partcol2=val2 ...)] select_sta
tement1 FROM from_statement;

hive (bigdata)> select
 
 * from student;
OK
student.id  student.name
1   zhangsan
2   lisi
Time taken: 4.057 seconds, Fetched: 2 row(s)
#直接新增資料
hive (bigdata)> insert into table student values('3','wangwu');
hive (bigdata)> select * from student;
OK
student.id  student.name
3   wangwu
1   zhangsan
2   lisi
Time taken: 0.326 seconds, Fetched: 3 row(s)
#從其他表載入資料
hive (bigdata)> create table student2(id int,name string)
              > row format delimited fields terminated by '\t';
hive (bigdata)> insert into table student2 values('4','chenliu');
hive (bigdata)> insert into table student select * from student2;
hive (bigdata)> select * from student;
OK
student.id  student.name
3   wangwu
4   chenliu
1   zhangsan
2   lisi
Time taken: 0.311 seconds, Fetched: 4 row(s)
#覆蓋掉原來表中資料
hive (bigdata)> insert overwrite table student select * from student2;
#將一個表的資料新增到其它多個表中
#以下三種結果相同，都不覆蓋原表資料
hive (bigdata)> from student2
              > insert overwrite table teacher partition(day=20180812) select *
              > insert into table teacher partition(day=20180813) select *;
hive (bigdata)> from student3
              > insert into table teacher partition(day=20180812) select *
              > insert overwrite table teacher partition(day=20180813) select *;
hive (bigdata)> from student2
              > insert into table aaa partition(day=20180812) select *
              > insert into table aaa partition(day=20180813) select *;
#覆蓋原表資料
hive (bigdata)> from student3
              > insert overwrite table aaa partition(day='20180812') select *
              > insert overwrite table aaa partition(day='20180813') select *;

3、as select模式

hive (bigdata)> create table student4 as select * from teacher;

4、location模式

#本地上傳到hdfs
hive (bigdata)> dfs -put /opt/test/student /student;
#從hdfs匯入
hive (bigdata)> create table student5(id int,name string)
              > row format delimited fields terminated by '\t'
              > location '/student';

5.import模式

#匯入的必須是經過export匯出的資料
hive (wangfang)> import table teacher from '/yyy';

資料匯出

1、insert模式

#匯出到本地
hive (bigdata)> insert overwrite local directory '/opt/test/export'
              > select * from teacher;
[[email protected] export]# more 000000_0 
4chenliu20180812
5wangfang20180812
1zhangsan20180812
2lisi20180812
4chenliu20180813
5wangfang20180813
1zhangsan20180813
2lisi20180813
#匯出到本地，新增格式
hive (bigdata)> insert overwrite local directory '/opt/test/export'
              > row format delimited fields terminated by '\t'
              > select * from teacher;
[[email protected] export]# more 000000_0 
4   chenliu 20180812
5   wangfang    20180812
1   zhangsan    20180812
2   lisi    20180812
4   chenliu 20180813
5   wangfang    20180813
1   zhangsan    20180813
2   lisi    20180813
#匯出到HDFS
hive (bigdata)> insert overwrite directory '/xxx'
              > row format delimited fields terminated by '\t'
              > select * from teacher;

2、export模式

#匯出路徑目錄需不存在，匯出是自行建立
hive (bigdata)> export table teacher to '/yyy';

3、dfs -get模式

hive (bigdata)> dfs -get /hive/warehouse/bigdata.db/student/000000_0 /opt/test/export/aaa.txt

4、hive -e 模式

[[email protected] export]# hive -e 'select * from student;' > /opt/test/export/bbb.txt;