二、分桶且桶内排序(clustered by+sorted by) sorted by是需要与clustered by一起用的,不能单独用 1、建表 create table test_bucket_sorted ( id int comment 'ID', name string comment '名字' ) comment '测试分桶' clustered by(id) sorted by (id) into 4 buckets ROW FORMAT DELIMITED FIELDS TER...
hive> create table tbl_user(id bigint, name string) clustered by(id) sorted by (id) into 4 buckets row format delimited fields terminated by "," lines terminated by "\n"; hive> create table tbl_user_tmp(id bigint, name string) row format delimited fields terminated by "," lines ter...
在 Hive 中，我们可以通过 CLUSTERED BY 指定分桶列，并通过 SORTED BY 指定桶中数据的排序参考列。下面为分桶表建表语句示例：CREATE EXTERNAL TABLE emp_bucket( empno INT, ename STRING, job STRING, mgr INT, hiredate TIMESTAMP, sal DECIMAL(7,2), comm DECIMAL(7,2), dept...
-- Produces rows clustered by age. Persons with same age are clustered together. -- In the query below, persons with age 18 and 25 are in first partition and the -- persons with age 16 are in the second partition. The rows are sorted based -- on age within each partition. SELECT ag...
CLUSTERED BY和SORTED BY创建命令不会影响数据如何插入表中 - 只会影响它的读取方式。这意味着用户必须小心地通过指定减少器的数量等于桶的数量并在查询中使用CLUSTER BY和SORT BY命令来正确插入数据。 连接两个在(包含连接列)相同列上划分了桶的表,可以使用map端连接(map-side join)高效的实现。比如join操作。对于...
CREATE [EXTERNAL] TABLE [IF NOT EXISTS] table_name [(col_name data_type [COMMENT col_comment], ...)] [COMMENT table_comment] [PARTITIONED BY (col_name data_type [COMMENT col_comment], ...)] [CLUSTERED BY (col_name, col_name, ...) [SORTED BY (col_name [ASC|DESC], ...)]...
clustered by(id) sorted by(id) into 6 buckets row format delimited fields terminated by '\t'; load data local inpath '/opt/module/data/bigtable' into table bigtable_buck1; 4 )创建分通表 2 ,分桶数和第一张表的分桶数为倍数关系 ...
by中，所有的set reducer都会在内部对数据进行排序，然后再合并在一起，这样可以提高性能。而在order by...
CREATEEXTERNALTABLEemp_bucket(empnoINT,enameSTRING,jobSTRING,mgrINT,hiredateTIMESTAMP,salDECIMAL(7,2),commDECIMAL(7,2),deptnoINT)CLUSTEREDBY(empno)SORTEDBY(empnoASC)INTO4BUCKETS--按照员工编号散列到四个 bucket 中ROWFORMATDELIMITEDFIELDSTERMINATEDBY"\t"LOCATION'/hive/emp_bucket'; ...
CLUSTERED BY(empno) SORTED BY(empno ASC) INTO 4 BUCKETS --按照员工编号散列到四个 bucket 中 ROW FORMAT DELIMITED FIELDS TERMINATED BY "\t" LOCATION '/hive/emp_bucket'; 1.4 加载数据到分桶表 这里直接使用Load语句向分桶表加载数据,数据时可以加载成功的,但是数据并不会分桶。 这是由于分桶的实质...