Pinot connector#

The Pinot connector allows Trino to query data stored in Apache Pinot™.

Requirements#

To connect to Pinot, you need:

  • Pinot 0.10.0 or higher.

  • Network access from the Trino coordinator and workers to the Pinot controller nodes. Port 8098 is the default port.

Configuration#

To configure the Pinot connector, create a catalog properties file e.g. etc/catalog/pinot.properties with at least the following contents:

connector.name=pinot
pinot.controller-urls=host1:8098,host2:8098

Replace host1:8098,host2:8098 with a comma-separated list of Pinot controller nodes. This can be the ip or the FDQN, the url scheme (http://) is optional.

Configuration properties#

General configuration properties#

Property name

Required

Description

pinot.controller-urls

Yes

A comma separated list of controller hosts. If Pinot is deployed via Kubernetes this needs to point to the controller service endpoint. The Pinot broker and server must be accessible via DNS as Pinot returns hostnames and not IP addresses.

pinot.connection-timeout

No

Pinot connection timeout, default is 15s.

pinot.metadata-expiry

No

Pinot metadata expiration time, default is 2m.

pinot.request-timeout

No

The timeout for Pinot requests. Increasing this can reduce timeouts if DNS resolution is slow.

pinot.controller.authentication.type

No

Pinot authentication method for controller requests. Allowed values are NONE and PASSWORD - defaults to NONE which is no authentication.

pinot.controller.authentication.user

No

Controller username for basic authentication method.

pinot.controller.authentication.password

No

Controller password for basic authentication method.

pinot.broker.authentication.type

No

Pinot authentication method for broker requests. Allowed values are NONE and PASSWORD - defaults to NONE which is no authentication.

pinot.broker.authentication.user

No

Broker username for basic authentication method.

pinot.broker.authentication.password

No

Broker password for basic authentication method.

pinot.max-rows-per-split-for-segment-queries

No

Fail query if Pinot server split returns more rows than configured, default to 50,000 for non-gRPC connection, 2,147,483,647 for gRPC connection.

pinot.estimated-size-in-bytes-for-non-numeric-column

No

Estimated byte size for non-numeric column for page pre-allocation in non-gRPC connection, default is 20.

pinot.prefer-broker-queries

No

Pinot query plan prefers to query Pinot broker, default is true.

pinot.forbid-segment-queries

No

Forbid parallel querying and force all querying to happen via the broker, default is false.

pinot.segments-per-split

No

The number of segments processed in a split. Setting this higher reduces the number of requests made to Pinot. This is useful for smaller Pinot clusters, default is 1.

pinot.fetch-retry-count

No

Retry count for retriable Pinot data fetch calls, default is 2.

pinot.non-aggregate-limit-for-broker-queries

No

Max limit for non aggregate queries to the Pinot broker, default is 25,000.

pinot.max-rows-for-broker-queries

No

Max rows for a broker query can return, default is 50,000.

pinot.aggregation-pushdown.enabled

No

Push down aggregation queries, default is true.

pinot.count-distinct-pushdown.enabled

No

Push down count distinct queries to Pinot, default is true.

pinot.target-segment-page-size

No

Max allowed page size for segment query, default is 1MB.

pinot.proxy.enabled

No

Use Pinot Proxy for controller and broker requests, default is false.

If pinot.controller.authentication.type is set to PASSWORD then both pinot.controller.authentication.user and pinot.controller.authentication.password are required.

If pinot.broker.authentication.type is set to PASSWORD then both pinot.broker.authentication.user and pinot.broker.authentication.password are required.

If pinot.controller-urls uses https scheme then TLS is enabled for all connections including brokers.

gRPC configuration properties#

Property name

Required

Description

pinot.grpc.enabled

No

Use gRPC endpoint for Pinot server queries, default is true.

pinot.grpc.port

No

Pinot gRPC port, default to 8090.

pinot.grpc.max-inbound-message-size

No

Max inbound message bytes when init gRPC client, default is 128MB.

pinot.grpc.use-plain-text

No

Use plain text for gRPC communication, default to true.

pinot.grpc.tls.keystore-type

No

TLS keystore type for gRPC connection, default is JKS.

pinot.grpc.tls.keystore-path

No

TLS keystore file location for gRPC connection, default is empty.

pinot.grpc.tls.keystore-password

No

TLS keystore password, default is empty.

pinot.grpc.tls.truststore-type

No

TLS truststore type for gRPC connection, default is JKS.

pinot.grpc.tls.truststore-path

No

TLS truststore file location for gRPC connection, default is empty.

pinot.grpc.tls.truststore-password

No

TLS truststore password, default is empty.

pinot.grpc.tls.ssl-provider

No

SSL provider, default is JDK.

pinot.grpc.proxy-uri

No

Pinot Rest Proxy gRPC endpoint URI, default is null.

For more Apache Pinot TLS configurations, please also refer to Configuring TLS/SSL.

You can use secrets to avoid actual values in the catalog properties files.

Querying Pinot tables#

The Pinot connector automatically exposes all tables in the default schema of the catalog. You can list all tables in the pinot catalog with the following query:

SHOW TABLES FROM pinot.default;

You can list columns in the flight_status table:

DESCRIBE pinot.default.flight_status;
SHOW COLUMNS FROM pinot.default.flight_status;

Queries written with SQL are fully supported and can include filters and limits:

SELECT foo
FROM pinot_table
WHERE bar = 3 AND baz IN ('ONE', 'TWO', 'THREE')
LIMIT 25000;

Dynamic tables#

To leverage Pinot’s fast aggregation, a Pinot query written in PQL can be used as the table name. Filters and limits in the outer query are pushed down to Pinot. Let’s look at an example query:

SELECT *
FROM pinot.default."SELECT MAX(col1), COUNT(col2) FROM pinot_table GROUP BY col3, col4"
WHERE col3 IN ('FOO', 'BAR') AND col4 > 50
LIMIT 30000

Filtering and limit processing is pushed down to Pinot.

The queries are routed to the broker and are more suitable to aggregate queries.

For SELECT queries without aggregates it is more performant to issue a regular SQL query. Processing is routed directly to the servers that store the data.

The above query is translated to the following Pinot PQL query:

SELECT MAX(col1), COUNT(col2)
FROM pinot_table
WHERE col3 IN('FOO', 'BAR') and col4 > 50
TOP 30000

Type mapping#

Because Trino and Pinot each support types that the other does not, this connector maps some types when reading data.

Pinot type to Trino type mapping#

The connector maps Pinot types to the corresponding Trino types according to the following table:

Pinot type to Trino type mapping#

Pinot type

Trino type

INT

INTEGER

LONG

BIGINT

FLOAT

REAL

DOUBLE

DOUBLE

STRING

VARCHAR

BYTES

VARBINARY

JSON

JSON

TIMESTAMP

TIMESTAMP

INT_ARRAY

VARCHAR

LONG_ARRAY

VARCHAR

FLOAT_ARRAY

VARCHAR

DOUBLE_ARRAY

VARCHAR

STRING_ARRAY

VARCHAR

Pinot does not allow null values in any data type.

No other types are supported.

SQL support#

The connector provides globally available and read operation statements to access data and metadata in Pinot.

Pushdown#

The connector supports pushdown for a number of operations:

Aggregate pushdown for the following functions:

Aggregate function pushdown is enabled by default, but can be disabled with the catalog property pinot.aggregation-pushdown.enabled or the catalog session property aggregation_pushdown_enabled.

A count(distint) pushdown may cause Pinot to run a full table scan with significant performance impact. If you encounter this problem, you can disable it with the catalog property pinot.count-distinct-pushdown.enabled or the catalog session property count_distinct_pushdown_enabled.