文章目录
- 1. 分区操作
- 1.1 查询分区信息
- 1.2 添加分区
- 1.3 删除分区
- 1.4 修改分区
- 2.列操作
- 3. 表操作
- 3.1 创建外部表
- 3.2 修改表属性
- 3.3 表的重命名
- 4. Ref
1. 分区操作
1.1 查询分区信息
代码语言:javascript
复制show partitions t_test;
describe formatted t_test partition (sample_date="20190723", partition_name="7");
show table extended like 't_test' partition (sample_date="20190723",partition_name="7");
show partitions t_test PARTITION(sample_date=20190826, partition_name=9);
1.2 添加分区
代码语言:javascript
复制ALTER TABLE table_name ADD PARTITION (partCol = 'value1') location 'loc1'; //示例
ALTER TABLE table_name ADD IF NOT EXISTS PARTITION (dt='20130101') LOCATION '/user/hadoop/warehouse/table_name/dt=20130101'; //一次添加一个分区
ALTER TABLE page_view ADD PARTITION (dt='2008-08-08', country='us') location '/path/to/us/part080808' PARTITION (dt='2008-08-09', country='us') location '/path/to/us/part080809'; //一次添加多个分区
1.3 删除分区
代码语言:javascript
复制ALTER TABLE login DROP IF EXISTS PARTITION (dt='2008-08-08');
ALTER TABLE page_view DROP IF EXISTS PARTITION (dt='2008-08-08', country='us');
1.4 修改分区
代码语言:javascript
复制ALTER TABLE table_name PARTITION (dt='2008-08-08') SET LOCATION "new location";
ALTER TABLE table_name PARTITION (dt='2008-08-08') RENAME TO PARTITION (dt='20080808');
2.列操作
2.1 添加列
代码语言:javascript
复制ALTER TABLE table_name ADD COLUMNS (col_name STRING); //在所有存在的列后面,但是在分区列之前添加一列
2.2 修改列
代码语言:javascript
复制CREATE TABLE test_change (a int, b int, c int);
// will change column a's name to a1
ALTER TABLE test_change CHANGE a a1 INT;
// will change column a's name to a1, a's data type to string, and put it after column b. The new table's structure is: b int, a1 string, c int
ALTER TABLE test_change CHANGE a a1 STRING AFTER b;
// will change column b's name to b1, and put it as the first column. The new table's structure is: b1 int, a string, c int
ALTER TABLE test_change CHANGE b b1 INT FIRST;
3. 表操作
3.1 创建外部表
代码语言:javascript
复制CREATE EXTERNAL TABLE `t_test`(
`row_key` string,
`type` string,
`time` string,
`id` string)
PARTITIONED BY (
`date` string,
`partition` string)
3.2 修改表属性
代码语言:javascript
复制alter table table_name set TBLPROPERTIES ('EXTERNAL'='TRUE'); //内部表转外部表
alter table table_name set TBLPROPERTIES ('EXTERNAL'='FALSE'); //外部表转内部表
3.3 表的重命名
代码语言:javascript
复制ALTER TABLE table_name RENAME TO new_table_name
4. Ref
- https://cwiki.apache.org/confluence/display/Hive/LanguageManual DDL#LanguageManualDDL-Add/ReplaceColumns