1
0
Files
hudi/docs/quickstart.md
2017-04-03 21:27:49 -07:00

191 lines
5.3 KiB
Markdown

---
title: Quickstart
keywords: quickstart
tags: [quickstart]
sidebar: mydoc_sidebar
permalink: quickstart.html
---
## Download Hoodie
Check out code and pull it into Intellij as a normal maven project.
Normally build the maven project, from command line
```
$ mvn clean install -DskipTests
```
{% include callout.html content="You might want to add your spark assembly jar to project dependencies under 'Module Setttings', to be able to run Spark from IDE" type="info" %}
{% include note.html content="Setup your local hadoop/hive test environment, so you can play with entire ecosystem. See [this](http://www.bytearray.io/2016/05/setting-up-hadoopyarnsparkhive-on-mac.html) for reference" %}
## Generate a Hoodie Dataset
Create the output folder on your local HDFS
```
hdfs dfs -mkdir -p /tmp/hoodie/sample-table
```
You can run the __HoodieClientExample__ class, to place a two commits (commit 1 => 100 inserts, commit 2 => 100 updates to previously inserted 100 records) onto your HDFS at /tmp/hoodie/sample-table
```
hdfs dfs -copyFromLocal /tmp/hoodie/sample-table/* /tmp/hoodie/sample-table
```
## Register Dataset to Hive Metastore
Now, lets see how we can publish this data into Hive.
#### Starting up Hive locally
```
hdfs namenode # start name node
hdfs datanode # start data node
bin/hive --service metastore -p 10000 # start metastore
bin/hiveserver2 \
--hiveconf hive.server2.thrift.port=10010 \
--hiveconf hive.root.logger=INFO,console \
--hiveconf hive.aux.jars.path=hoodie/hoodie-hadoop-mr/target/hoodie-hadoop-mr-0.3.6-SNAPSHOT.jar
```
#### Hive Sync Tool
Once Hive is up and running, the sync tool can be used to sync commits done above to a Hive table, as follows.
```
java -cp target/hoodie-hive-0.3.1-SNAPSHOT-jar-with-dependencies.jar:target/jars/* com.uber.hoodie.hive.HiveSyncTool \
--base-path file:///tmp/hoodie/sample-table/ \
--database default \
--table hoodie_test \
--user hive \
--pass hive \
--jdbc-url jdbc:hive2://localhost:10010/
```
#### Manually via Beeline
Add in the hoodie-hadoop-mr jar so, Hive can read the Hoodie dataset and answer the query.
```
hive> add jar file:///tmp/hoodie-hadoop-mr-0.2.7.jar;
Added [file:///tmp/hoodie-hadoop-mr-0.2.7.jar] to class path
Added resources: [file:///tmp/hoodie-hadoop-mr-0.2.7.jar]
```
Then, you need to create a ReadOptimized table as below (only type supported as of now)and register the sample partitions
```
drop table hoodie_test;
CREATE EXTERNAL TABLE hoodie_test(`_row_key` string,
`_hoodie_commit_time` string,
`_hoodie_commit_seqno` string,
rider string,
driver string,
begin_lat double,
begin_lon double,
end_lat double,
end_lon double,
fare double)
PARTITIONED BY (`datestr` string)
ROW FORMAT SERDE
'org.apache.hadoop.hive.ql.io.parquet.serde.ParquetHiveSerDe'
STORED AS INPUTFORMAT
'com.uber.hoodie.hadoop.HoodieInputFormat'
OUTPUTFORMAT
'org.apache.hadoop.hive.ql.io.parquet.MapredParquetOutputFormat'
LOCATION
'hdfs:///tmp/hoodie/sample-table';
ALTER TABLE `hoodie_test` ADD IF NOT EXISTS PARTITION (datestr='2016-03-15') LOCATION 'hdfs:///tmp/hoodie/sample-table/2016/03/15';
ALTER TABLE `hoodie_test` ADD IF NOT EXISTS PARTITION (datestr='2015-03-16') LOCATION 'hdfs:///tmp/hoodie/sample-table/2015/03/16';
ALTER TABLE `hoodie_test` ADD IF NOT EXISTS PARTITION (datestr='2015-03-17') LOCATION 'hdfs:///tmp/hoodie/sample-table/2015/03/17';
set mapreduce.framework.name=yarn;
```
## Querying The Dataset
Now, we can proceed to query the dataset, as we would normally do across all the three query engines supported.
### HiveQL
Let's first perform a query on the latest committed snapshot of the table
```
hive> select count(*) from hoodie_test;
...
OK
100
Time taken: 18.05 seconds, Fetched: 1 row(s)
hive>
```
### SparkSQL
Spark is super easy, once you get Hive working as above. Just spin up a Spark Shell as below
```
$ cd $SPARK_INSTALL
$ export HADOOP_CONF_DIR=$HADOOP_HOME/etc/hadoop
$ spark-shell --jars /tmp/hoodie-hadoop-mr-0.2.7.jar --driver-class-path $HADOOP_CONF_DIR --conf spark.sql.hive.convertMetastoreParquet=false
scala> val sqlContext = new org.apache.spark.sql.SQLContext(sc)
scala> sqlContext.sql("show tables").show(10000)
scala> sqlContext.sql("describe hoodie_test").show(10000)
scala> sqlContext.sql("select count(*) from hoodie_test").show(10000)
```
### Presto
Checkout the 'master' branch on OSS Presto, build it, and place your installation somewhere.
* Copy the hoodie-hadoop-mr-0.2.7 jar into $PRESTO_INSTALL/plugin/hive-hadoop2/
* Startup your server and you should be able to query the same Hive table via Presto
```
show columns from hive.default.hoodie_test;
select count(*) from hive.default.hoodie_test
```
## Incremental Queries
Let's now perform a query, to obtain the __ONLY__ changed rows since a commit in the past.
```
hive> set hoodie.hoodie_test.consume.mode=INCREMENTAL;
hive> set hoodie.hoodie_test.consume.start.timestamp=001;
hive> set hoodie.hoodie_test.consume.max.commits=10;
hive> select `_hoodie_commit_time`, rider, driver from hoodie_test where `_hoodie_commit_time` > '001' limit 10;
OK
All commits :[001, 002]
002 rider-001 driver-001
002 rider-001 driver-001
002 rider-002 driver-002
002 rider-001 driver-001
002 rider-001 driver-001
002 rider-002 driver-002
002 rider-001 driver-001
002 rider-002 driver-002
002 rider-002 driver-002
002 rider-001 driver-001
Time taken: 0.056 seconds, Fetched: 10 row(s)
hive>
hive>
```