druid/docs/content/development/extensions-contrib/orc.md

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---
layout: doc_page
---
# Orc
To use this extension, make sure to [include](../../operations/including-extensions.html) `druid-orc-extensions`.
This extension enables Druid to ingest and understand the Apache Orc data format offline.
## Orc Hadoop Parser
This is for batch ingestion using the HadoopDruidIndexer. The inputFormat of inputSpec in ioConfig must be set to `"org.apache.hadoop.hive.ql.io.orc.OrcNewInputFormat"`.
Field | Type | Description | Required
----------|-------------|----------------------------------------------------------------------------------------|---------
type | String | This should say `orc` | yes
parseSpec | JSON Object | Specifies the timestamp and dimensions of the data. Any parse spec that extends ParseSpec is possible but only their TimestampSpec and DimensionsSpec are used. | yes
typeString| String | String representation of Orc struct type info. If not specified, auto constructed from parseSpec but all metric columns are dropped | no
For example of `typeString`, string column col1 and array of string column col2 is represented by `"struct<col1:string,col2:array<string>>"`.
Currently, it only supports java primitive types and array of java primitive types, which means only 'list' of compound types in [ORC types](https://orc.apache.org/docs/types.html) is supported (list of list is not supported).
For example of hadoop indexing:
```json
{
"type": "index_hadoop",
"spec": {
"ioConfig": {
"type": "hadoop",
"inputSpec": {
"type": "static",
"inputFormat": "org.apache.hadoop.hive.ql.io.orc.OrcNewInputFormat",
"paths": "/data/path/in/HDFS/"
},
"metadataUpdateSpec": {
"type": "postgresql",
"connectURI": "jdbc:postgresql://localhost/druid",
"user" : "druid",
"password" : "asdf",
"segmentTable": "druid_segments"
},
"segmentOutputPath": "tmp/segments"
},
"dataSchema": {
"dataSource": "no_metrics",
"parser": {
"type": "orc",
"parseSpec": {
"format": "timeAndDims",
"timestampSpec": {
"column": "time",
"format": "auto"
},
"dimensionsSpec": {
"dimensions": [
"name"
],
"dimensionExclusions": [],
"spatialDimensions": []
}
},
"typeString": "struct<time:string,name:string>"
},
"metricsSpec": [{
"type": "count",
"name": "count"
}],
"granularitySpec": {
"type": "uniform",
"segmentGranularity": "DAY",
"queryGranularity": "ALL",
"intervals": ["2015-12-31/2016-01-02"]
}
},
"tuningConfig": {
"type": "hadoop",
"workingPath": "tmp/working_path",
"partitionsSpec": {
"targetPartitionSize": 5000000
},
"jobProperties" : {},
"leaveIntermediate": true
}
}
}
```
Almost all the fields listed above are required, including `inputFormat`, `metadataUpdateSpec`(`type`, `connectURI`, `user`, `password`, `segmentTable`). Set `jobProperties` to make hdfs path timezone unrelated.