Paimon Catalog

Doris currently supports accessing Paimon table metadata through various metadata services and querying Paimon data.

At present, only read operations on Paimon tables are supported. Write operations to Paimon tables will be supported in the future.

Quick start with Apache Doris and Apache Paimon.

Applicable Scenarios

Scenario	Description
Query Acceleration	Use Doris's distributed computing engine to directly access Paimon data for query acceleration.
Data Integration	Read Paimon data and write it into Doris internal tables, or perform ZeroETL operations using the Doris computing engine.
Data Write-back	Not supported yet.

Configuring Catalog

Syntax

CREATE CATALOG [IF NOT EXISTS] catalog_name PROPERTIES (
    'type' = 'paimon',
    'paimon.catalog.type' = '<paimon_catalog_type>',
    'warehouse' = '<paimon_warehouse>'
    {MetaStoreProperties},
    {StorageProperties},
    {CommonProperties}
);

• <paimon_catalog_type>

  The type of Paimon Catalog, supporting the following:

  • filesystem: Default. Directly accesses metadata stored on the file system.

  • hms: Uses Hive Metastore as the metadata service.

  • dlf: Uses Alibaba Cloud DLF as the metadata service.

• <paimon_warehouse>

  The warehouse path for Paimon. This parameter must be specified when <paimon_catalog_type> is filesystem.

  The warehouse path must point to the level above the Database path. For example, if your table path is: s3://bucket/path/to/db1/table1, then warehouse should be: s3://bucket/path/to/.

• {MetaStoreProperties}

  The MetaStoreProperties section is used to fill in connection and authentication information for the Metastore metadata service. Refer to the section on [Supported Metadata Services] for details.

• {StorageProperties}

  The StorageProperties section is used to fill in connection and authentication information related to the storage system. Refer to the section on [Supported Storage Systems] for details.

• {CommonProperties}

  The CommonProperties section is used to fill in common properties. Please refer to the Catalog Overview section on [Common Properties].

Supported Paimon Versions

The currently dependent Paimon version is 1.0.0.

Supported Paimon Formats

• Supports reading Paimon Deletion Vector

Supported Metadata Services

• Hive Metastore

• Aliyun DLF

• FileSystem

Supported Storage Systems

• HDFS

• AWS S3

• Google Cloud Storage

• Alibaba Cloud OSS

• Tencent Cloud COS

• Huawei Cloud OBS

• MINIO

Supported Data Formats

• Parquet

• ORC

Column Type Mapping

Paimon Type	Doris Type	Comment
boolean	boolean
tinyint	tinyint
smallint	smallint
integer	int
bigint	bigint
float	float
double	double
decimal(P, S)	decimal(P, S)
varchar	string
char	string
binary	string
varbinary	string
date	date
timestamp_without_time_zone	datetime(N)	Mapped according to precision. If precision is greater than 6, it maps to a maximum of 6 (may cause precision loss).
timestamp_with_local_time_zone	datetime(N)	Mapped according to precision. If precision is greater than 6, it maps to a maximum of 6 (may cause precision loss).
array	array
map	map
row	struct
other	UNSUPPORTED

Examples

Paimon on HDFS

CREATE CATALOG paimon_hdfs PROPERTIES (
    'type' = 'paimon',
    'warehouse' = 'hdfs://HDFS8000871/user/paimon',
    'dfs.nameservices' = 'HDFS8000871',
    'dfs.ha.namenodes.HDFS8000871' = 'nn1,nn2',
    'dfs.namenode.rpc-address.HDFS8000871.nn1' = '172.21.0.1:4007',
    'dfs.namenode.rpc-address.HDFS8000871.nn2' = '172.21.0.2:4007',
    'dfs.client.failover.proxy.provider.HDFS8000871' = 'org.apache.hadoop.hdfs.server.namenode.ha.ConfiguredFailoverProxyProvider',
    'hadoop.username' = 'hadoop'
);

Paimon on HMS

CREATE CATALOG paimon_hms PROPERTIES (
    'type' = 'paimon',
    'paimon.catalog.type' = 'hms',
    'warehouse' = 'hdfs://HDFS8000871/user/zhangdong/paimon2',
    'hive.metastore.uris' = 'thrift://172.21.0.44:7004',
    'dfs.nameservices' = 'HDFS8000871',
    'dfs.ha.namenodes.HDFS8000871' = 'nn1,nn2',
    'dfs.namenode.rpc-address.HDFS8000871.nn1' = '172.21.0.1:4007',
    'dfs.namenode.rpc-address.HDFS8000871.nn2' = '172.21.0.2:4007',
    'dfs.client.failover.proxy.provider.HDFS8000871' = 'org.apache.hadoop.hdfs.server.namenode.ha.ConfiguredFailoverProxyProvider',
    'hadoop.username' = 'hadoop'
);

Paimon on DLF

CREATE CATALOG paimon_dlf PROPERTIES (
    'type' = 'paimon',
    'paimon.catalog.type' = 'dlf',
    'warehouse' = 'oss://xx/yy/',
    'dlf.proxy.mode' = 'DLF_ONLY',
    'dlf.uid' = 'xxxxx',
    'dlf.region' = 'cn-beijing',
    'dlf.access_key' = 'ak',
    'dlf.secret_key' = 'sk'
);

Query Operations

Basic Query

Once the Catalog is configured, you can query the table data in the Catalog as follows:

-- 1. Switch to catalog, use database, and query
SWITCH paimon_ctl;
USE paimon_db;
SELECT * FROM paimon_tbl LIMIT 10;

-- 2. Use Paimon database directly
USE paimon_ctl.paimon_db;
SELECT * FROM paimon_tbl LIMIT 10;

-- 3. Use fully qualified name to query
SELECT * FROM paimon_ctl.paimon_db.paimon_tbl LIMIT 10;

Appendix