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Version: Latest-3.2

Paimon catalog

StarRocks supports Paimon catalogs from v3.1 onwards.

A Paimon catalog is a kind of external catalog that enables you to query data from Apache Paimon without ingestion.

Also, you can directly transform and load data from Paimon by using INSERT INTO based on Paimon catalogs.

To ensure successful SQL workloads on your Paimon cluster, your StarRocks cluster must be able to access the storage system and metastore of your Paimon cluster. StarRocks supports the following storage systems and metastores:

  • Distributed file system (HDFS) or object storage like AWS S3, Microsoft Azure Storage, Google GCS, or or other S3-compatible storage system (for example, MinIO)
  • Metastore like your file system or Hive metastore

Usage notes​

You can only use Paimon catalogs to query data. You cannot use Paimon catalogs to drop, delete, or insert data into your Paimon cluster.

Integration preparations​

Before you create a Paimon catalog, make sure your StarRocks cluster can integrate with the storage system and metastore of your Paimon cluster.

AWS IAM​

If your Paimon cluster uses AWS S3 as storage, choose your suitable authentication method and make the required preparations to ensure that your StarRocks cluster can access the related AWS cloud resources.

The following authentication methods are recommended:

  • Instance profile (recommended)
  • Assumed role
  • IAM user

Of the above-mentioned three authentication methods, instance profile is the most widely used.

For more information, see Preparation for authentication in AWS IAM.

HDFS​

If you choose HDFS as storage, configure your StarRocks cluster as follows:

  • (Optional) Set the username that is used to access your HDFS cluster and Hive metastore. By default, StarRocks uses the username of the FE and BE or CN processes to access your HDFS cluster and Hive metastore. You can also set the username by adding export HADOOP_USER_NAME="<user_name>" at the beginning of the fe/conf/hadoop_env.sh file of each FE and at the beginning of the be/conf/hadoop_env.sh file of each BE or the cn/conf/hadoop_env.sh file of each CN. After you set the username in these files, restart each FE and each BE or CN to make the parameter settings take effect. You can set only one username for each StarRocks cluster.
  • When you query Paimon data, the FEs and BEs or CNs of your StarRocks cluster use the HDFS client to access your HDFS cluster. In most cases, you do not need to configure your StarRocks cluster to achieve that purpose, and StarRocks starts the HDFS client using the default configurations. You need to configure your StarRocks cluster only in the following situations:
    • High availability (HA) is enabled for your HDFS cluster: Add the hdfs-site.xml file of your HDFS cluster to the $FE_HOME/conf path of each FE and to the $BE_HOME/conf path of each BE or the $CN_HOME/conf path of each CN.
    • View File System (ViewFs) is enabled for your HDFS cluster: Add the core-site.xml file of your HDFS cluster to the $FE_HOME/conf path of each FE and to the $BE_HOME/conf path of each BE or the $CN_HOME/conf path of each CN.

NOTE

If an error indicating an unknown host is returned when you send a query, you must add the mapping between the host names and IP addresses of your HDFS cluster nodes to the /etc/hosts path.

Kerberos authentication​

If Kerberos authentication is enabled for your HDFS cluster or Hive metastore, configure your StarRocks cluster as follows:

  • Run the kinit -kt keytab_path principal command on each FE and each BE or CN to obtain Ticket Granting Ticket (TGT) from Key Distribution Center (KDC). To run this command, you must have the permissions to access your HDFS cluster and Hive metastore. Note that accessing KDC with this command is time-sensitive. Therefore, you need to use cron to run this command periodically.
  • Add JAVA_OPTS="-Djava.security.krb5.conf=/etc/krb5.conf" to the $FE_HOME/conf/fe.conf file of each FE and to the $BE_HOME/conf/be.conf file of each BE or the $CN_HOME/conf/cn.conf file of each CN. In this example, /etc/krb5.conf is the save path of the krb5.conf file. You can modify the path based on your needs.

Create a Paimon catalog​

Syntax​

CREATE EXTERNAL CATALOG <catalog_name>
[COMMENT <comment>]
PROPERTIES
(
    "type" = "paimon",
    CatalogParams,
    StorageCredentialParams,
)

Parameters​

catalog_name​

The name of the Paimon catalog. The naming conventions are as follows:

  • The name can contain letters, digits (0-9), and underscores (_). It must start with a letter.
  • The name is case-sensitive and cannot exceed 1023 characters in length.

comment​

The description of the Paimon catalog. This parameter is optional.

type​

The type of your data source. Set the value to paimon.

CatalogParams​

A set of parameters about how StarRocks accesses the metadata of your Paimon cluster.

The following table describes the parameter you need to configure in CatalogParams.

ParameterRequiredDescription
paimon.catalog.typeYesThe type of metastore that you use for your Paimon cluster. Set this parameter to filesystem or hive.
paimon.catalog.warehouseYesThe warehouse storage path of your Paimon data.
hive.metastore.urisNoThe URI of your Hive metastore. Format: thrift://<metastore_IP_address>:<metastore_port>. If high availability (HA) is enabled for your Hive metastore, you can specify multiple metastore URIs and separate them with commas (,), for example, "thrift://<metastore_IP_address_1>:<metastore_port_1>,thrift://<metastore_IP_address_2>:<metastore_port_2>,thrift://<metastore_IP_address_3>:<metastore_port_3>".

NOTE

If you use Hive metastore, you must add the mapping between the host names and IP addresses of your Hive metastore nodes to the /etc/hosts path before you query Paimon data. Otherwise, StarRocks may fail to access your Hive metastore when you start a query.

StorageCredentialParams​

A set of parameters about how StarRocks integrates with your storage system. This parameter set is optional.

If you use HDFS as storage, you do not need to configure StorageCredentialParams.

If you use AWS S3, other S3-compatible storage system, Microsoft Azure Storage, or Google GCS as storage, you must configure StorageCredentialParams.

AWS S3​

If you choose AWS S3 as storage for your Paimon cluster, take one of the following actions:

  • To choose the instance profile-based authentication method, configure StorageCredentialParams as follows:

    "aws.s3.use_instance_profile" = "true",
    "aws.s3.region" = "<aws_s3_region>"

  • To choose the assumed role-based authentication method, configure StorageCredentialParams as follows:

    "aws.s3.use_instance_profile" = "true",
    "aws.s3.iam_role_arn" = "<iam_role_arn>",
    "aws.s3.region" = "<aws_s3_region>"

  • To choose the IAM user-based authentication method, configure StorageCredentialParams as follows:

    "aws.s3.use_instance_profile" = "false",
    "aws.s3.access_key" = "<iam_user_access_key>",
    "aws.s3.secret_key" = "<iam_user_secret_key>",
    "aws.s3.region" = "<aws_s3_region>"

The following table describes the parameters you need to configure in StorageCredentialParams.

ParameterRequiredDescription
aws.s3.use_instance_profileYesSpecifies whether to enable the instance profile-based authentication method and the assumed role-based authentication method. Valid values: true and false. Default value: false.
aws.s3.iam_role_arnNoThe ARN of the IAM role that has privileges on your AWS S3 bucket. If you use the assumed role-based authentication method to access AWS S3, you must specify this parameter.
aws.s3.regionYesThe region in which your AWS S3 bucket resides. Example: us-west-1.
aws.s3.access_keyNoThe access key of your IAM user. If you use the IAM user-based authentication method to access AWS S3, you must specify this parameter.
aws.s3.secret_keyNoThe secret key of your IAM user. If you use the IAM user-based authentication method to access AWS S3, you must specify this parameter.

For information about how to choose an authentication method for accessing AWS S3 and how to configure an access control policy in AWS IAM Console, see Authentication parameters for accessing AWS S3.

S3-compatible storage system​

If you choose an S3-compatible storage system, such as MinIO, as storage for your Paimon cluster, configure StorageCredentialParams as follows to ensure a successful integration:

"aws.s3.enable_ssl" = "false",
"aws.s3.enable_path_style_access" = "true",
"aws.s3.endpoint" = "<s3_endpoint>",
"aws.s3.access_key" = "<iam_user_access_key>",
"aws.s3.secret_key" = "<iam_user_secret_key>"

The following table describes the parameters you need to configure in StorageCredentialParams.

ParameterRequiredDescription
aws.s3.enable_sslYesSpecifies whether to enable SSL connection.
Valid values: true and false. Default value: true.
aws.s3.enable_path_style_accessYesSpecifies whether to enable path-style access.
Valid values: true and false. Default value: false. For MinIO, you must set the value to true.
Path-style URLs use the following format: https://s3.<region_code>.amazonaws.com/<bucket_name>/<key_name>. For example, if you create a bucket named DOC-EXAMPLE-BUCKET1 in the US West (Oregon) Region, and you want to access the alice.jpg object in that bucket, you can use the following path-style URL: https://s3.us-west-2.amazonaws.com/DOC-EXAMPLE-BUCKET1/alice.jpg.
aws.s3.endpointYesThe endpoint that is used to connect to your S3-compatible storage system instead of AWS S3.
aws.s3.access_keyYesThe access key of your IAM user.
aws.s3.secret_keyYesThe secret key of your IAM user.
Microsoft Azure Storage​
Azure Blob Storage​

If you choose Blob Storage as storage for your Paimon cluster, take one of the following actions:

  • To choose the Shared Key authentication method, configure StorageCredentialParams as follows:

    "azure.blob.storage_account" = "<storage_account_name>",
    "azure.blob.shared_key" = "<storage_account_shared_key>"

    The following table describes the parameters you need to configure in StorageCredentialParams.

    ParameterRequiredDescription
    azure.blob.storage_accountYesThe username of your Blob Storage account.
    azure.blob.shared_keyYesThe shared key of your Blob Storage account.

  • To choose the SAS Token authentication method, configure StorageCredentialParams as follows:

    "azure.blob.storage_account" = "<storage_account_name>",
    "azure.blob.container" = "<container_name>",
    "azure.blob.sas_token" = "<storage_account_SAS_token>"

    The following table describes the parameters you need to configure in StorageCredentialParams.

    ParameterRequiredDescription
    azure.blob.storage_accountYesThe username of your Blob Storage account.
    azure.blob.containerYesThe name of the blob container that stores your data.
    azure.blob.sas_tokenYesThe SAS token that is used to access your Blob Storage account.
Azure Data Lake Storage Gen2​

If you choose Data Lake Storage Gen2 as storage for your Paimon cluster, take one of the following actions:

  • To choose the Managed Identity authentication method, configure StorageCredentialParams as follows:

    "azure.adls2.oauth2_use_managed_identity" = "true",
    "azure.adls2.oauth2_tenant_id" = "<service_principal_tenant_id>",
    "azure.adls2.oauth2_client_id" = "<service_client_id>"

    The following table describes the parameters you need to configure in StorageCredentialParams.

    ParameterRequiredDescription
    azure.adls2.oauth2_use_managed_identityYesSpecifies whether to enable the Managed Identity authentication method. Set the value to true.
    azure.adls2.oauth2_tenant_idYesThe ID of the tenant whose data you want to access.
    azure.adls2.oauth2_client_idYesThe client (application) ID of the managed identity.

  • To choose the Shared Key authentication method, configure StorageCredentialParams as follows:

    "azure.adls2.storage_account" = "<storage_account_name>",
    "azure.adls2.shared_key" = "<storage_account_shared_key>"

    The following table describes the parameters you need to configure in StorageCredentialParams.

    ParameterRequiredDescription
    azure.adls2.storage_accountYesThe username of your Data Lake Storage Gen2 storage account.
    azure.adls2.shared_keyYesThe shared key of your Data Lake Storage Gen2 storage account.

  • To choose the Service Principal authentication method, configure StorageCredentialParams as follows:

    "azure.adls2.oauth2_client_id" = "<service_client_id>",
    "azure.adls2.oauth2_client_secret" = "<service_principal_client_secret>",
    "azure.adls2.oauth2_client_endpoint" = "<service_principal_client_endpoint>"

    The following table describes the parameters you need to configure in StorageCredentialParams.

    ParameterRequiredDescription
    azure.adls2.oauth2_client_idYesThe client (application) ID of the service principal.
    azure.adls2.oauth2_client_secretYesThe value of the new client (application) secret created.
    azure.adls2.oauth2_client_endpointYesThe OAuth 2.0 token endpoint (v1) of the service principal or application.
Azure Data Lake Storage Gen1​

If you choose Data Lake Storage Gen1 as storage for your Paimon cluster, take one of the following actions:

  • To choose the Managed Service Identity authentication method, configure StorageCredentialParams as follows:

    "azure.adls1.use_managed_service_identity" = "true"

    The following table describes the parameters you need to configure in StorageCredentialParams.

    ParameterRequiredDescription
    azure.adls1.use_managed_service_identityYesSpecifies whether to enable the Managed Service Identity authentication method. Set the value to true.

  • To choose the Service Principal authentication method, configure StorageCredentialParams as follows:

    "azure.adls1.oauth2_client_id" = "<application_client_id>",
    "azure.adls1.oauth2_credential" = "<application_client_credential>",
    "azure.adls1.oauth2_endpoint" = "<OAuth_2.0_authorization_endpoint_v2>"

    The following table describes the parameters you need to configure in StorageCredentialParams.

    ParameterRequiredDescription
    azure.adls1.oauth2_client_idYesThe client (application) ID of the service principal.
    azure.adls1.oauth2_credentialYesThe value of the new client (application) secret created.
    azure.adls1.oauth2_endpointYesThe OAuth 2.0 token endpoint (v1) of the service principal or application.
Google GCS​

If you choose Google GCS as storage for your Paimon cluster, take one of the following actions:

  • To choose the VM-based authentication method, configure StorageCredentialParams as follows:

    "gcp.gcs.use_compute_engine_service_account" = "true"

    The following table describes the parameters you need to configure in StorageCredentialParams.

    ParameterDefault valueValue exampleDescription
    gcp.gcs.use_compute_engine_service_accountFALSETRUESpecifies whether to directly use the service account that is bound to your Compute Engine.

  • To choose the service account-based authentication method, configure StorageCredentialParams as follows:

    "gcp.gcs.service_account_email" = "<google_service_account_email>",
    "gcp.gcs.service_account_private_key_id" = "<google_service_private_key_id>",
    "gcp.gcs.service_account_private_key" = "<google_service_private_key>"

    The following table describes the parameters you need to configure in StorageCredentialParams.

    ParameterDefault valueValue exampleDescription
    gcp.gcs.service_account_email"""user@hello.iam.gserviceaccount.com"The email address in the JSON file generated at the creation of the service account.
    gcp.gcs.service_account_private_key_id"""61d257bd8479547cb3e04f0b9b6b9ca07af3b7ea"The private key ID in the JSON file generated at the creation of the service account.
    gcp.gcs.service_account_private_key"""-----BEGIN PRIVATE KEY----xxxx-----END PRIVATE KEY-----\n"The private key in the JSON file generated at the creation of the service account.

  • To choose the impersonation-based authentication method, configure StorageCredentialParams as follows:

    • Make a VM instance impersonate a service account:

      "gcp.gcs.use_compute_engine_service_account" = "true",
      "gcp.gcs.impersonation_service_account" = "<assumed_google_service_account_email>"

      The following table describes the parameters you need to configure in StorageCredentialParams.

      ParameterDefault valueValue exampleDescription
      gcp.gcs.use_compute_engine_service_accountFALSETRUESpecifies whether to directly use the service account that is bound to your Compute Engine.
      gcp.gcs.impersonation_service_account"""hello"The service account that you want to impersonate.

    • Make a service account (temporarily named as meta service account) impersonate another service account (temporarily named as data service account):

      "gcp.gcs.service_account_email" = "<google_service_account_email>",
      "gcp.gcs.service_account_private_key_id" = "<meta_google_service_account_email>",
      "gcp.gcs.service_account_private_key" = "<meta_google_service_account_email>",
      "gcp.gcs.impersonation_service_account" = "<data_google_service_account_email>"

      The following table describes the parameters you need to configure in StorageCredentialParams.

      ParameterDefault valueValue exampleDescription
      gcp.gcs.service_account_email"""user@hello.iam.gserviceaccount.com"The email address in the JSON file generated at the creation of the meta service account.
      gcp.gcs.service_account_private_key_id"""61d257bd8479547cb3e04f0b9b6b9ca07af3b7ea"The private key ID in the JSON file generated at the creation of the meta service account.
      gcp.gcs.service_account_private_key"""-----BEGIN PRIVATE KEY----xxxx-----END PRIVATE KEY-----\n"The private key in the JSON file generated at the creation of the meta service account.
      gcp.gcs.impersonation_service_account"""hello"The data service account that you want to impersonate.

Examples​

The following examples create a Paimon catalog named paimon_catalog_fs whose metastore type paimon.catalog.type is set to filesystem to query data from your Paimon cluster.

AWS S3​

  • If you choose the instance profile-based authentication method, run a command like below:

    CREATE EXTERNAL CATALOG paimon_catalog_fs
    PROPERTIES
    (
        "type" = "paimon",
        "paimon.catalog.type" = "filesystem",
        "paimon.catalog.warehouse" = "<s3_paimon_warehouse_path>",
        "aws.s3.use_instance_profile" = "true",
        "aws.s3.region" = "us-west-2"
    );

  • If you choose the assumed role-based authentication method, run a command like below:

    CREATE EXTERNAL CATALOG paimon_catalog_fs
    PROPERTIES
    (
        "type" = "paimon",
        "paimon.catalog.type" = "filesystem",
        "paimon.catalog.warehouse" = "<s3_paimon_warehouse_path>",
        "aws.s3.use_instance_profile" = "true",
        "aws.s3.iam_role_arn" = "arn:aws:iam::081976408565:role/test_s3_role",
        "aws.s3.region" = "us-west-2"
    );

  • If you choose the IAM user-based authentication method, run a command like below:

    CREATE EXTERNAL CATALOG paimon_catalog_fs
    PROPERTIES
    (
        "type" = "paimon",
        "paimon.catalog.type" = "filesystem",
        "paimon.catalog.warehouse" = "<s3_paimon_warehouse_path>",
        "aws.s3.use_instance_profile" = "false",
        "aws.s3.access_key" = "<iam_user_access_key>",
        "aws.s3.secret_key" = "<iam_user_secret_key>",
        "aws.s3.region" = "us-west-2"
    );

S3-compatible storage system​

Use MinIO as an example. Run a command like below:

CREATE EXTERNAL CATALOG paimon_catalog_fs
PROPERTIES
(
    "type" = "paimon",
    "paimon.catalog.type" = "filesystem",
    "paimon.catalog.warehouse" = "<paimon_warehouse_path>",
    "aws.s3.enable_ssl" = "true",
    "aws.s3.enable_path_style_access" = "true",
    "aws.s3.endpoint" = "<s3_endpoint>",
    "aws.s3.access_key" = "<iam_user_access_key>",
    "aws.s3.secret_key" = "<iam_user_secret_key>"
);

Microsoft Azure Storage​

Azure Blob Storage​

  • If you choose the Shared Key authentication method, run a command like below:

    CREATE EXTERNAL CATALOG paimon_catalog_fs
    PROPERTIES
    (
        "type" = "paimon",
        "paimon.catalog.type" = "filesystem",
        "paimon.catalog.warehouse" = "<blob_paimon_warehouse_path>",
        "azure.blob.storage_account" = "<blob_storage_account_name>",
        "azure.blob.shared_key" = "<blob_storage_account_shared_key>"
    );

  • If you choose the SAS Token authentication method, run a command like below:

    CREATE EXTERNAL CATALOG paimon_catalog_fs
    PROPERTIES
    (
        "type" = "paimon",
        "paimon.catalog.type" = "filesystem",
        "paimon.catalog.warehouse" = "<blob_paimon_warehouse_path>",
        "azure.blob.storage_account" = "<blob_storage_account_name>",
        "azure.blob.container" = "<blob_container_name>",
        "azure.blob.sas_token" = "<blob_storage_account_SAS_token>"
    );
Azure Data Lake Storage Gen1​

  • If you choose the Managed Service Identity authentication method, run a command like below:

    CREATE EXTERNAL CATALOG paimon_catalog_fs
    PROPERTIES
    (
        "type" = "paimon",
        "paimon.catalog.type" = "filesystem",
        "paimon.catalog.warehouse" = "<adls1_paimon_warehouse_path>",
        "azure.adls1.use_managed_service_identity" = "true"
    );

  • If you choose the Service Principal authentication method, run a command like below:

    CREATE EXTERNAL CATALOG paimon_catalog_fs
    PROPERTIES
    (
        "type" = "paimon",
        "paimon.catalog.type" = "filesystem",
        "paimon.catalog.warehouse" = "<adls1_paimon_warehouse_path>",
        "azure.adls1.oauth2_client_id" = "<application_client_id>",
        "azure.adls1.oauth2_credential" = "<application_client_credential>",
        "azure.adls1.oauth2_endpoint" = "<OAuth_2.0_authorization_endpoint_v2>"
    );
Azure Data Lake Storage Gen2​

  • If you choose the Managed Identity authentication method, run a command like below:

    CREATE EXTERNAL CATALOG paimon_catalog_fs
    PROPERTIES
    (
        "type" = "paimon",
        "paimon.catalog.type" = "filesystem",
        "paimon.catalog.warehouse" = "<adls2_paimon_warehouse_path>",
        "azure.adls2.oauth2_use_managed_identity" = "true",
        "azure.adls2.oauth2_tenant_id" = "<service_principal_tenant_id>",
        "azure.adls2.oauth2_client_id" = "<service_client_id>"
    );

  • If you choose the Shared Key authentication method, run a command like below:

    CREATE EXTERNAL CATALOG paimon_catalog_fs
    PROPERTIES
    (
        "type" = "paimon",
        "paimon.catalog.type" = "filesystem",
        "paimon.catalog.warehouse" = "<adls2_paimon_warehouse_path>",
        "azure.adls2.storage_account" = "<storage_account_name>",
        "azure.adls2.shared_key" = "<shared_key>"
    );

  • If you choose the Service Principal authentication method, run a command like below:

    CREATE EXTERNAL CATALOG paimon_catalog_fs
    PROPERTIES
    (
        "type" = "paimon",
        "paimon.catalog.type" = "filesystem",
        "paimon.catalog.warehouse" = "<adls2_paimon_warehouse_path>",
        "azure.adls2.oauth2_client_id" = "<service_client_id>",
        "azure.adls2.oauth2_client_secret" = "<service_principal_client_secret>",
        "azure.adls2.oauth2_client_endpoint" = "<service_principal_client_endpoint>"
    );

Google GCS​

  • If you choose the VM-based authentication method, run a command like below:

    CREATE EXTERNAL CATALOG paimon_catalog_fs
    PROPERTIES
    (
        "type" = "paimon",
        "paimon.catalog.type" = "filesystem",
        "paimon.catalog.warehouse" = "<gcs_paimon_warehouse_path>",
        "gcp.gcs.use_compute_engine_service_account" = "true"
    );

  • If you choose the service account-based authentication method, run a command like below:

    CREATE EXTERNAL CATALOG paimon_catalog_fs
    PROPERTIES
    (
        "type" = "paimon",
        "paimon.catalog.type" = "filesystem",
        "paimon.catalog.warehouse" = "<gcs_paimon_warehouse_path>",
        "gcp.gcs.service_account_email" = "<google_service_account_email>",
        "gcp.gcs.service_account_private_key_id" = "<google_service_private_key_id>",
        "gcp.gcs.service_account_private_key" = "<google_service_private_key>"
    );

  • If you choose the impersonation-based authentication method:

    • If you make a VM instance impersonate a service account, run a command like below:

      CREATE EXTERNAL CATALOG paimon_catalog_fs
      PROPERTIES
      (
          "type" = "paimon",
          "paimon.catalog.type" = "filesystem",
          "paimon.catalog.warehouse" = "<gcs_paimon_warehouse_path>",
          "gcp.gcs.use_compute_engine_service_account" = "true",
          "gcp.gcs.impersonation_service_account" = "<assumed_google_service_account_email>"
      );

    • If you make a service account impersonate another service account, run a command like below:

      CREATE EXTERNAL CATALOG paimon_catalog_fs
      PROPERTIES
      (
          "type" = "paimon",
          "paimon.catalog.type" = "filesystem",
          "paimon.catalog.warehouse" = "<gcs_paimon_warehouse_path>",
          "gcp.gcs.service_account_email" = "<google_service_account_email>",
          "gcp.gcs.service_account_private_key_id" = "<meta_google_service_account_email>",
          "gcp.gcs.service_account_private_key" = "<meta_google_service_account_email>",
          "gcp.gcs.impersonation_service_account" = "<data_google_service_account_email>"
      );

View Paimon catalogs​

You can use SHOW CATALOGS to query all catalogs in the current StarRocks cluster:

SHOW CATALOGS;

You can also use SHOW CREATE CATALOG to query the creation statement of an external catalog. The following example queries the creation statement of a Paimon catalog named paimon_catalog_fs:

SHOW CREATE CATALOG paimon_catalog_fs;

Drop a Paimon catalog​

You can use DROP CATALOG to drop an external catalog.

The following example drops a Paimon catalog named paimon_catalog_fs:

DROP Catalog paimon_catalog_fs;

View the schema of a Paimon table​

You can use one of the following syntaxes to view the schema of a Paimon table:

  • View schema

    DESC[RIBE] <catalog_name>.<database_name>.<table_name>;

  • View schema and location from the CREATE statement

    SHOW CREATE TABLE <catalog_name>.<database_name>.<table_name>;

Query a Paimon table​

  1. Use SHOW DATABASES to view the databases in your Paimon cluster:

    SHOW DATABASES FROM <catalog_name>;

  2. Use SET CATALOG to switch to the destination catalog in the current session:

    SET CATALOG <catalog_name>;

    Then, use USE to specify the active database in the current session:

    USE <db_name>;

    Or, you can use USE to directly specify the active database in the destination catalog:

    USE <catalog_name>.<db_name>;

  3. Use SELECT to query the destination table in the specified database:

    SELECT count(*) FROM <table_name> LIMIT 10;

Load data from Paimon​

Suppose you have an OLAP table named olap_tbl, you can transform and load data like below:

INSERT INTO default_catalog.olap_db.olap_tbl SELECT * FROM paimon_table;