This is a quick&dirty implementation of a MongoDB storage handler for Apache HIVE.

##CAUTION:

• currently only support Hive primitive types: string, int, smallint....

• Whitespace should not be used in between entries in the "mongo.column.mapping" string, since these will be interperted as part of the column name, which is not what you want.

• if you want "insert overwrite" feature, you must have a field named be mapped to "_id" field (Object Id in MongoDB collections).

Some code are borrowed/referenced from Balshor's Google Spreadsheet Handler(https://github.com/balshor/gdata-storagehandler) and HyperTable Hive extension(http://code.google.com/p/hypertable/wiki/HiveExtension), thanks for the help.

##How to build Here's a simple guide on how to build, hope it helps(thanks WalterDalton for providing the information):

• 1. make sure you have java sdk installed (otherwise download and install from http://www.oracle.com/technetwork/java/index.html) , $JAVA_HOME env variable is point to the installed directory and $JAVA_HOME/bin/ is included in $PATH env variable;
• 2. download maven from http://maven.apache.org and install to a directory (let's say $MAVEN_HOME), add $MAVEN_HOME/bin to $PATH
• 3. git clone Hive-Mongo to a directory; launch a cmd shell, cd that directory and execute "mvn package"; if everything is OK, you can find "hive-mongo-0.0.1-SNAPSHOT.jar" in the "target" directory. There also have a jar named "hive-mongo-0.0.1-SNAPSHOT-jar-with-dependencies.jar" which is a combo; with this one you do not need to include mongo-java-driver-2.6.3.jar and guava-r06.jar.

##Sample Usage:

> $HIVE_HOME/bin/hive --auxpath /home/yc.huang/mongo-java-driver-2.6.3.jar,/home/yc.huang/guava-r06.jar,  
/home/yc.huang/hive-mongo-0.0.1-SNAPSHOT.jar


hive> create external table mongo_users(id int, name string, age int)  
stored by "org.yong3.hive.mongo.MongoStorageHandler"  
with serdeproperties ( "mongo.column.mapping" = "_id,name,age" )  
tblproperties ( "mongo.host" = "192.168.0.5", "mongo.port" = "11211",  
"mongo.db" = "test", "mongo.collection" = "users" );

OK
Time taken: 4.093 seconds



hive> insert overwrite table mongo_users select id, name,age from hive_test;



Total MapReduce jobs = 1

Launching Job 1 out of 1

Number of reduce tasks is set to 0 since there's no reduce operator

Starting Job = job_201111021553_13715, Tracking URL = http://JobTracker:50030/jobdetails.jsp?jobid=job_201111021553_13715

Kill Command = /root/dev/hadoop-0.20.2/bin/../bin/hadoop job  -Dmapred.job.tracker=JobTracker:9001 -kill job_201111021553_13715

2011-11-17 18:01:25,849 Stage-0 map = 0%,  reduce = 0%

2011-11-17 18:01:28,876 Stage-0 map = 100%,  reduce = 0%

2011-11-17 18:01:31,893 Stage-0 map = 100%,  reduce = 100%

Ended Job = job_201111021553_13715

4 Rows loaded to mongo_users

OK

Time taken: 14.37 seconds

hive> select * from mongo_users;



OK



1       Tom     28

2       Alice   18

3       Bob     29

101     Scott   10

Time taken: 0.171 seconds