CREATE ICEBERG TABLE (Iceberg REST catalog)¶

Syntax¶

CREATE [ OR REPLACE ] ICEBERG TABLE [ IF NOT EXISTS ] <table_name>
  [ EXTERNAL_VOLUME = '<external_volume_name>' ]
  [ CATALOG = '<catalog_integration_name>' ]
  CATALOG_TABLE_NAME = '<rest_catalog_table_name>'
  [ CATALOG_NAMESPACE = '<catalog_namespace>' ]
  [ REPLACE_INVALID_CHARACTERS = { TRUE | FALSE } ]
  [ AUTO_REFRESH = { TRUE | FALSE } ]
  [ COMMENT = '<string_literal>' ]
  [ [ WITH ] TAG ( <tag_name> = '<tag_value>' [ , <tag_name> = '<tag_value>' , ... ] ) ]
  [ WITH CONTACT ( <purpose> = <contact_name> [ , <purpose> = <contact_name> ... ] ) ]

Variant syntax¶

CREATE ICEBERG TABLE [ IF NOT EXISTS ] <table_name>
  [
    --Column definition
    <col_name> <col_type>
      [ [ WITH ] MASKING POLICY <policy_name> [ USING ( <col_name> , <cond_col1> , ... ) ] ]

    -- Additional column definitions
    [ , <col_name> <col_type> [ ... ] ]
  ]
  [ MAX_DATA_EXTENSION_TIME_IN_DAYS = <integer> ]
  [ AUTO_REFRESH = { TRUE | FALSE } ]
  [ REPLACE_INVALID_CHARACTERS = { TRUE | FALSE } ]
  [ COPY GRANTS ]
  [ COMMENT = '<string_literal>' ]
  [ [ WITH ] TAG ( <tag_name> = '<tag_value>' [ , <tag_name> = '<tag_value>' , ... ] ) ]

Required parameters¶

table_name

Specifies the identifier (name) for the table in Snowflake; must be unique for the schema in which the table is created.

In addition, the identifier must start with an alphabetic character and cannot contain spaces or special characters unless the entire identifier string is enclosed in double quotes (for example, "My object"). Identifiers enclosed in double quotes are also case-sensitive.

For more information, see Identifier requirements.

Note

To retrieve a list of tables or namespaces in your remote catalog, you can use the following functions:

• SYSTEM$LIST_ICEBERG_TABLES_FROM_CATALOG

• SYSTEM$LIST_NAMESPACES_FROM_CATALOG

CATALOG_TABLE_NAME = 'rest_catalog_table_name'

Specifies the table name as recognized by your external catalog. This parameter can’t be changed after you create the table.

Note

Don’t specify a namespace with the table name (mynamespace.mytable). To specify a namespace for this table, and override the default namespace set for the catalog integration, use the CATALOG_NAMESPACE parameter.

col_name

For creating a table in a catalog-linked database (preview).

Specifies a column identifier (name). All the requirements for table identifiers also apply to column identifiers.

For more information, see Identifier requirements and Reserved & limited keywords.

Note

In addition to the standard reserved keywords, the following keywords can’t be used as column identifiers because they are reserved for ANSI-standard context functions:

• CURRENT_DATE

• CURRENT_ROLE

• CURRENT_TIME

• CURRENT_TIMESTAMP

• CURRENT_USER

For the list of reserved keywords, see Reserved & limited keywords.

col_type

For creating a table in a catalog-linked database (preview).

Specifies the data type for the column.

For information about the data types that can be specified for table columns, see Data types for Apache Iceberg™ tables.

Optional parameters¶

MASKING POLICY = policy_name

For creating a table in a catalog-linked database (preview).

Specifies the masking policy to set on a column. The masking policy must belong to a standard Snowflake database (not the catalog-linked database).

EXTERNAL_VOLUME = 'external_volume_name'

Specifies the identifier (name) for the external volume where the Iceberg table stores its metadata files and data in Parquet format. Iceberg metadata and manifest files store the table schema, partitions, snapshots, and other metadata.

If you don’t specify this parameter, the Iceberg table defaults to the external volume for the schema, database, or account. The schema takes precedence over the database, and the database takes precedence over the account.

CATALOG = 'catalog_integration_name'

Specifies the identifier (name) of the catalog integration for this table.

If you don’t specify this parameter, the Iceberg table defaults to the catalog integration for the schema, database, or account. The schema takes precedence over the database, and the database takes precedence over the account.

CATALOG_NAMESPACE = 'catalog_namespace'

• Optionally specifies the namespace (for example, my_database) for the REST catalog source. By specifying a namespace with the catalog integration and then at the table level, you can use a single REST catalog integration to create Iceberg tables across different databases. If you don’t specify a namespace with the table, the table uses the default catalog namespace associated with the catalog integration.

• If a default namespace isn’t specified with the catalog integration, you must specify the namespace for the REST catalog source to set a catalog namespace for the table.

Note

To retrieve a list of tables or namespaces in your remote catalog, you can use the following functions:

• SYSTEM$LIST_ICEBERG_TABLES_FROM_CATALOG

• SYSTEM$LIST_NAMESPACES_FROM_CATALOG

MAX_DATA_EXTENSION_TIME_IN_DAYS = integer

Object parameter that specifies the maximum number of days for which Snowflake can extend the data retention period for the table to prevent streams on the table from becoming stale.

For a detailed description of this parameter, see MAX_DATA_EXTENSION_TIME_IN_DAYS.

REPLACE_INVALID_CHARACTERS = { TRUE | FALSE }

Specifies whether to replace invalid UTF-8 characters with the Unicode replacement character (�) in query results. You can only set this parameter for tables that use an external Iceberg catalog.

• TRUE replaces invalid UTF-8 characters with the Unicode replacement character.

• FALSE leaves invalid UTF-8 characters unchanged. Snowflake returns a user error message when it encounters invalid UTF-8 characters in a Parquet data file.

If not specified, the Iceberg table defaults to the parameter value for the schema, database, or account. The schema takes precedence over the database, and the database takes precedence over the account.

Default: FALSE

AUTO_REFRESH = { TRUE | FALSE }

Specifies whether Snowflake should automatically poll the external Iceberg catalog that is associated with the table for metadata updates.

If no value is specified for the REFRESH_INTERVAL_SECONDS parameter on the catalog integration, Snowflake uses a default refresh interval of 30 seconds.

For more information, see automated refresh.

Default: FALSE

Note

Using AUTO_REFRESH with INFER_SCHEMA isn’t supported.

COPY GRANTS

Specifies to retain the access privileges from the original table when a new table is created using any of the following CREATE TABLE variants:

• CREATE OR REPLACE TABLE

The parameter copies all privileges, except OWNERSHIP, from the existing table to the new table. The new table does not inherit any future grants defined for the object type in the schema. By default, the role that executes the CREATE TABLE statement owns the new table.

If the parameter is not included in the CREATE ICEBERG TABLE statement, then the new table does not inherit any explicit access privileges granted on the original table, but does inherit any future grants defined for the object type in the schema.

Note:

• With data sharing:

  • If the existing table was shared to another account, the replacement table is also shared.

  • If the existing table was shared with your account as a data consumer, and access was further granted to other roles in the account (using GRANT IMPORTED PRIVILEGES on the parent database), access is also granted to the replacement table.

• The SHOW GRANTS output for the replacement table lists the grantee for the copied privileges as the role that executed the CREATE ICEBERG TABLE statement, with the current timestamp when the statement was executed.

• The operation to copy grants occurs atomically in the CREATE ICEBERG TABLE command (that is, within the same transaction).

COMMENT = 'string_literal'

Specifies a comment for the table.

Default: No value

TAG ( tag_name = 'tag_value' [ , tag_name = 'tag_value' , ... ] )

Specifies the tag name and the tag string value.

The tag value is always a string, and the maximum number of characters for the tag value is 256.

For information about specifying tags in a statement, see Tag quota for objects.

WITH CONTACT ( purpose = contact [ , purpose = contact ...] )

Preview Feature — Open

Available to all accounts.

Associate the new object with one or more contacts.

Access control requirements¶

A role used to execute this operation must have the following privileges at a minimum:

The USAGE privilege on the parent database and schema are required to perform operations on any object in a schema.

For instructions on creating a custom role with a specified set of privileges, see Creating custom roles.

For general information about roles and privilege grants for performing SQL actions on securable objects, see Overview of Access Control.

Usage notes¶

• If you created your external volume or catalog integration using a double-quoted identifier, you must specify the identifier exactly as created (including the double quotes) in your CREATE ICEBERG TABLE statement. Failure to include the quotes might result in an Object does not exist error (or similar type of error).

• For creating an Iceberg table with write support (preview):

  • If you use a standard Snowflake database, you must first create an Iceberg table in your remote catalog. For example, you might use Spark to write an Iceberg table to Open Catalog. Don’t specify column definitions in your CREATE ICEBERG TABLE statement.

  • If you use a catalog-linked database, you must specify column definitions when you create the table. Alternatively, you can write to Iceberg tables that Snowflake automatically discovers in your remote catalog.

• Considerations for creating tables:

  • A schema cannot contain tables and/or views with the same name. When creating a table:

    • If a view with the same name already exists in the schema, an error is returned and the table is not created.

    • If a table with the same name already exists in the schema, an error is returned and the table is not created, unless the optional OR REPLACE keyword is included in the command.

  • CREATE OR REPLACE <object> statements are atomic. That is, when an object is replaced, the old object is deleted and the new object is created in a single transaction.

    This means that any queries concurrent with the CREATE OR REPLACE ICEBERG TABLE operation use either the old or new table version.

  • The OR REPLACE and IF NOT EXISTS clauses are mutually exclusive. They can’t both be used in the same statement.

  • Similar to reserved keywords, ANSI-reserved function names (CURRENT_DATE, CURRENT_TIMESTAMP, etc.) cannot be used as column names.

  • Recreating a table (using the optional OR REPLACE keyword) drops its history, which makes any stream on the table stale. A stale stream is unreadable.

• Regarding metadata:

  Attention

  Customers should ensure that no personal data (other than for a User object), sensitive data, export-controlled data, or other regulated data is entered as metadata when using the Snowflake service. For more information, see Metadata fields in Snowflake.

Examples¶

CREATE OR REPLACE ICEBERG TABLE my_iceberg_table
  EXTERNAL_VOLUME = 'my_external_volume'
  CATALOG = 'my_rest_catalog_integration'
  CATALOG_TABLE_NAME = 'my_remote_table'
  AUTO_REFRESH = TRUE;

CREATE ICEBERG TABLE open_catalog_iceberg_table
  EXTERNAL_VOLUME = 'my_external_volume'
  CATALOG = 'open_catalog_int'
  CATALOG_TABLE_NAME = 'my_open_catalog_table'
  AUTO_REFRESH = TRUE;

USE DATABASE my_catalog_linked_db;

USE SCHEMA 'my_namespace';

CREATE OR REPLACE ICEBERG TABLE my_iceberg_table (
  first_name string,
  last_name string,
  amount int,
  create_date date
);