hive DDL语法汇总
1、对表重命名
hive> ALTER TABLE table_name RENAME TO new_table_name;
2、修改表备注
hive> ALTER
TABLE
table_name
SET
TBLPROPERTIES (
'comment'
= new_comment);
3、添加表分区
hive> ALTER TABLE table_name ADD [IF NOT EXISTS] PARTITION partition_spec
[LOCATION
'location1'
] partition_spec [LOCATION
'location2'
] ...;
hive> 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'
;
5、交换分区(0.12版本以上支持)
两个表结构必需相同,
hive> ALTER TABLE table_name_1 EXCHANGE PARTITION (partition_spec) WITH TABLE table_name_2;
6、删除表分区
ALTER TABLE table_name DROP [IF EXISTS] PARTITION partition_spec[, PARTITION partition_spec, ...]
[IGNORE PROTECTION] [PURGE];
注意:PURGE 参数是在Hive
1.2
.
0及以后的版本才支持,加上该参数则直接删除表分区,而不是将数据放入垃圾回收站;如果没加purge参数,则删掉的分区进入回收站
ALTER TABLE table_name ARCHIVE PARTITION partition_spec;
ALTER TABLE table_name UNARCHIVE PARTITION partition_spec;
9、修改列
ALTER TABLE table_name [PARTITION partition_spec] CHANGE [COLUMN] col_old_name col_new_name column_type [COMMENT col_comment] [FIRST|AFTER column_name] [CASCADE|RESTRICT];
例子:
CREATE TABLE test_change (a
int
, b
int
, c
int
);
// First change column a's name to a1.
ALTER TABLE test_change CHANGE a a1 INT;
// Next change column a1's name to a2, its data type to string, and put it after column b.
ALTER TABLE test_change CHANGE a1 a2 STRING AFTER b;
// The new table's structure is: b int, a2 string, c int.
// Then change column c's name to c1, and put it as the first column.
ALTER TABLE test_change CHANGE c c1 INT FIRST;
// The new table's structure is: c1 int, b int, a2 string.
10、增加列
ALTER TABLE table_name [PARTITION partition_spec]
ADD|REPLACE COLUMNS (col_name data_type [COMMENT col_comment], ...)
[CASCADE|RESTRICT]