Hive學習總結之三:HiveQL介紹DML

第二部分：DML

DML包含以下操做：

•向數據表內加載文件

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

Load 操做只是單純的複製/移動操做，將數據文件移動到 Hive 表對應的位置。 filepath 1.相對路徑，例如：project/data1 2.絕對路徑，例如： /user/hive/project/data1 3.包含模式的完整 URI，例如：hdfs://namenode:9000/user/hive/project/data1

•將查詢結果插入到Hive表中

基本模式	INSERT OVERWRITE TABLE tablename1 [PARTITION (partcol1=val1, partcol2=val2 ...)] select_statement1 FROM from_statement
多插入模式	FROM from_statement INSERT OVERWRITE TABLE tablename1 [PARTITION (partcol1=val1, partcol2=val2 ...)] select_statement1 [INSERT OVERWRITE TABLE tablename2 [PARTITION ...] select_statement2] ...
自動分區模式	INSERT OVERWRITE TABLE tablename PARTITION (partcol1[=val1], partcol2[=val2] ...) select_statement FROM from_statement
將查詢結果寫入HDFS文件系統	INSERT OVERWRITE [LOCAL] DIRECTORY directory1 SELECT ... FROM ... FROM from_statement INSERT OVERWRITE [LOCAL] DIRECTORY directory1 select_statement1 [INSERT OVERWRITE [LOCAL] DIRECTORY directory2 select_statement2]
INSERT INTO	INSERT INTO  TABLE tablename1 [PARTITION (partcol1=val1, partcol2=val2 ...)] select_statement1 FROM from_statement