# Presto

Start running [Presto Image](https://hub.docker.com/repository/docker/apachepinot/pinot-presto) with pre-built [Presto Pinot connector](https://prestodb.io/docs/current/connector/pinot.html).

{% tabs %}
{% tab title="Docker" %}
Run below command to start a standalone Presto coordinator.

```
docker run \
  --network pinot-demo \
  --name=presto-coordinator \
  -p 8080:8080 \
  -d apachepinot/pinot-presto:latest
```

Then you can connect to presto with [Presto-Cli](https://prestodb.io/docs/current/installation/cli.html).

```
if [[ ! -f "/tmp/presto-cli" ]]; then
    curl -L https://repo1.maven.org/maven2/com/facebook/presto/presto-cli/0.228/presto-cli-0.228-executable.jar -o /tmp/presto-cli
    chmod +x /tmp/presto-cli
fi
/tmp/presto-cli --server localhost:8080 --catalog pinot_quickstart --schema default
```

Then write your own queries;

```
presto:default> show tables;
    Table
--------------
 airlinestats
(1 row)

Query 20200211_185652_00006_w6yfz, FINISHED, 1 node
Splits: 19 total, 19 done (100.00%)
0:00 [1 rows, 29B] [3 rows/s, 99B/s]
```

```
presto:default> select count(*) as flights_from_ca_to_ny from airlinestats where originstate='CA' and deststate='NY';
 flights_from_ca_to_ny
-----------------------
                    67
(1 row)

Query 20200211_190136_00018_w6yfz, FINISHED, 1 node
Splits: 17 total, 17 done (100.00%)
0:00 [1 rows, 8B] [5 rows/s, 42B/s]
```

```
presto:default> select * from airlinestats limit 1;
 flightnum | origin | quarter | lateaircraftdelay | divactualelapsedtime | divwheelsons | divwheelsoffs | airtime | arrdel15 | divtotalgtimes | deptimeblk | destcitymarketid | divairportseqids | dayssinceepoch | deptime | month | crselapsedtime | deststatename | carrier |
-----------+--------+---------+-------------------+----------------------+--------------+---------------+---------+----------+----------------+------------+------------------+------------------+----------------+---------+-------+----------------+---------------+---------+
       122 | DFW    |       1 |       -2147483648 |          -2147483648 |              |               |     202 |        0 |                | 0700-0759  |            32457 |                  |          16088 |     715 |     1 |            235 | California    | AA      |
(1 row)

Query 20200211_185719_00007_w6yfz, FINISHED, 1 node
Splits: 17 total, 17 done (100.00%)
0:02 [1 rows, 325B] [0 rows/s, 133B/s]
```

Meanwhile you can access [Presto Cluster UI](http://localhost:8080/ui/) to see query stats.

![Presto Cluster UI](https://630770001-files.gitbook.io/~/files/v0/b/gitbook-legacy-files/o/assets%2F-LtH6nl58DdnZnelPdTc%2F-M0_DYGdXBoKh_h0UmiL%2F-M0_EtbhtFuuAPKcZrDa%2Fimage.png?alt=media\&token=1acaf34f-61cb-41fc-b528-77944581ba4c)
{% endtab %}
{% endtabs %}

### Advanced features

### Using Pinot Streaming/gRPC connector

Presto supports aggregation and predicate push down to Pinot. However, for certain queries that Pinot doesn't handle, Presto tries to fetch all the rows from the Pinot table segment by segment. This is definitely not an ideal access pattern for Pinot.

In order to support large data scanning, Pinot (>=0.6.0) introduces a gRPC server for on-demand data scanning with a reasonable smaller memory footprint.

You can enable it by adding the below configs to the Pinot server config file:

```
pinot.server.grpc.enable=true
pinot.server.grpc.port=8090
```

Then you can enable the streaming connector in Presto(>=0.244) by adding the below config to the Pinot catalog configs.

```
pinot.use-streaming-for-segment-queries=true
```

(Disclaimer: Presto is a third-party software that is not part of the Apache Software Foundation).


---

# Agent Instructions: Querying This Documentation

If you need additional information that is not directly available in this page, you can query the documentation dynamically by asking a question.

Perform an HTTP GET request on the current page URL with the `ask` query parameter:

```
GET https://docs.pinot.apache.org/release-0.11.0/integrations/presto.md?ask=<question>
```

The question should be specific, self-contained, and written in natural language.
The response will contain a direct answer to the question and relevant excerpts and sources from the documentation.

Use this mechanism when the answer is not explicitly present in the current page, you need clarification or additional context, or you want to retrieve related documentation sections.