Hive_Hive的數據模型_內部表

Hive的數據模型_內部表

- 與數據庫中的Table在概念上是類似。
- 每一個Table在Hive中都有一個相應的目錄存儲數據。
- 所有的Table數據(不包括External Table)都保存在這個目錄中。

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create table t1
(tid int, tname string, age int);create table t2
(tid int, tname string, age int)
location '/mytable/hive/t2'create table t3
(tid int, tname string, age int)
row format delimited fields terminated by ',';create table t4
as
select * from t1;

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hdfs dfs -cat /usr/hive/warehouse/tablename/000000_0

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alter table t1 add columns(english int);
desc t1;

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if open the recycle bin function of hdfs . we can see the file has not been deleted, but move from one dir to another dir, we can restore it.

drop table t1;

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