> ## Documentation Index
> Fetch the complete documentation index at: https://docs.startree.ai/llms.txt
> Use this file to discover all available pages before exploring further.

# How to Combine Source Fields into one Column

In this recipe we'll learn how to combine the data from fields in our data source into a single column in Apache Pinot.

| Pinot Version | 0.10.0                                                                                                                      |
| ------------- | --------------------------------------------------------------------------------------------------------------------------- |
| Code          | [startreedata/pinot-recipes/combine-fields](https://github.com/startreedata/pinot-recipes/tree/main/recipes/combine-fields) |

## Prerequisites

To follow the code examples in this guide, you must [install Docker](https://docs.docker.com/get-docker/) locally and download recipes.

## Navigate to recipe

1. If you haven't already, download recipes.
2. In terminal, go to the recipe by running the following command:

```bash theme={null}
cd pinot-recipes/recipes/combine-fields
```

## Launch Pinot Cluster

You can spin up a Pinot Cluster by running the following command:

```bash theme={null}
docker-compose up
```

This command will run a single instance of the Pinot Controller, Pinot Server, Pinot Broker, and Zookeeper. You can find the [docker-compose.yml](https://github.com/startreedata/pinot-recipes/blob/main/recipes/json-unnest/docker-compose.yml) file on GitHub.

## Dataset

We're going to import the following JSON file:

```json theme={null}
{"name":"Pete", "surname": "Smith"}
{"name":"John", "surname": "Jones"}
```

*data/movies.json*

## Pinot Schema and Table

Now let's create a Pinot Schema and Table.

First, the schema:

```json theme={null}
{
  "schemaName": "people",
  "dimensionFieldSpecs": [
    {
      "name": "fullName",
      "dataType": "STRING"
    }
  ]
}
```

*config/schema.json*

You can create the schema by running the following command:

```bash theme={null}
docker exec -it pinot-controller-json bin/pinot-admin.sh AddSchema \
  -schemaFile /config/schema.json \
  -exec
```

We'll also have the following table config:

```json {9-14} theme={null}
{
  "tableName": "people",
  "tableType": "OFFLINE",
  "segmentsConfig": {
    "replication": 1,
    "schemaName": "people"
  },
  "ingestionConfig": {
    "transformConfigs": [
      {
        "columnName": "fullName",
        "transformFunction": "concat(name, surname, ' ')"
      }
    ],
    "batchIngestionConfig": {
      "segmentIngestionType": "APPEND",
      "segmentIngestionFrequency": "DAILY"
    }
  },
  "tenants": {
    "broker": "DefaultTenant",
    "server": "DefaultTenant"
  },
  "tableIndexConfig": {
    "loadMode": "MMAP"
  },
  "metadata": {}
}
```

*config/table.json*

The highlighted section contains a [transformation function](https://docs.pinot.apache.org/developers/advanced/ingestion-level-transformations) that concatenates the `name` and `surname` fields, separated by a space.

You can create the table by running the following command:\`

```bash theme={null}
docker exec -it pinot-controller-json bin/pinot-admin.sh AddTable \
  -tableConfigFile /config/table.json \
  -exec
```

## Ingestion Job

Now we’re going to import the JSON file into Pinot. We'll do this with the following ingestion spec:

```yaml theme={null}
executionFrameworkSpec:
  name: 'standalone'
  segmentGenerationJobRunnerClassName: 'org.apache.pinot.plugin.ingestion.batch.standalone.SegmentGenerationJobRunner'
  segmentTarPushJobRunnerClassName: 'org.apache.pinot.plugin.ingestion.batch.standalone.SegmentTarPushJobRunner'
jobType: SegmentCreationAndTarPush
inputDirURI: '/data'
includeFileNamePattern: 'glob:**/import.json'
outputDirURI: '/opt/pinot/data/people/'
overwriteOutput: true
pinotFSSpecs:
  - scheme: file
    className: org.apache.pinot.spi.filesystem.LocalPinotFS
recordReaderSpec:
  dataFormat: 'json'
  className: 'org.apache.pinot.plugin.inputformat.json.JSONRecordReader'
tableSpec:
  tableName: 'people'
pinotClusterSpecs:
  - controllerURI: 'http://pinot-controller-combine:9000'
pushJobSpec:
  pushAttempts: 2
  pushRetryIntervalMillis: 1000
```

*config/job-spec.yml*

You can run the following command to run the import:

```bash theme={null}
docker exec -it pinot-controller-json bin/pinot-admin.sh LaunchDataIngestionJob \
  -jobSpecFile /config/job-spec.yml
```

## Querying

Once that's completed, navigate to [localhost:9000/#/query](http://localhost:9000/#/query) and click on the `people` table or copy/paste the following query:

```sql theme={null}
select * 
from people 
```

You will see the following output:

| fullName   |
| ---------- |
| Pete Smith |
| John Jones |

*Query Results*

We can see that the `name` and `surname` fields from our JSON file have been combined into a single `fullName` column for each person.