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sp_data_source_objects (Transact-SQL)

Applies to: SQL Server 2019 (15.x)

Returns list of table objects that are available to be virtualized.

Syntax

Transact-SQL syntax conventions

sp_data_source_objects
        [ @data_source = ] 'data_source'
    [ , [ @object_root_name = ] 'object_root_name' ]
    [ , [ @max_search_depth = ] max_search_depth ]
    [ , [ @search_options = ] 'search_options' ]
[ ; ]

Arguments

[ @data_source = ] 'data_source'

The name of the external data source to get the metadata from. @data_source is sysname.

[ @object_root_name = ] 'object_root_name'

This parameter is the root of the name of the object(s) to search for. @object_root_name is nvarchar(max), with a default of NULL.

This call only returns external objects that begin with the value set for @object_root_name.

If an ODBC data source connects to a relational database management system (RDBMS) that uses three-part names, @object_root_name can't contain a partial database name. In these cases, the parameter @object_root_name should contain all three parts, with the third part being the object name to search.

Caution

Due to differences between external data platforms, some platforms don't return any results if the default value of NULL is provided. Some treat NULL as the lack of a filter. For example, Oracle RDMBS will not return results if NULL is provided for @object_root_name.

[ @max_search_depth = ] max_search_depth

This value specifies the maximum depth (in parts) past the @object_root_name that we wish to search. @max_search_depth is an int with a default of 1.

For example, a @max_search_depth of 1, with an @object_root_name that is the name of a SQL Server database, would return schemata contained inside the database.

A @max_search_depth of NULL returns information about @object_root_name if it exists and is non-empty, in the case of catalog or schema.

[ @search_options = ] 'search_options'

The search_options parameter is nvarchar(max) with a default of NULL.

This parameter isn't used but might be implemented in the future.

Result set

Column name Data type Description
OBJECT_TYPE nvarchar(200) The type of the object (Example: TABLE or DATABASE).
OBJECT_NAME nvarchar(max) The fully qualified name of the object. Escaped using backend-specific quote character.
OBJECT_LEAF_NAME nvarchar(max) The unqualified object name.
TABLE_LOCATION nvarchar(max) A valid table location string that could be used for the CREATE EXTERNAL TABLE statement. Is NULL if it isn't applicable.

Permissions

Requires ALTER ANY EXTERNAL DATA SOURCE permission.

Remarks

The SQL Server instance must have the PolyBase feature installed. This procedure was first introduced in SQL Server 2019 CU5.

This stored procedure supports connectors for:

  • SQL Server
  • Oracle
  • Teradata
  • MongoDB
  • Azure Cosmos DB

The stored procedure doesn't support generic ODBC data source or Hadoop connectors.

The notion of empty vs. non-empty relates to the behavior of the ODBC driver and the SQLTables function. Non-empty indicates an object contains tables, not rows. For example, an empty schema contains no tables in SQL Server. An empty database contains with no tables inside Teradata.

Object types are determined by the external data source's ODBC driver. Each external data source determines what qualifies as a table. This can include database objects like functions in Teradata, or synonyms in Oracle. PolyBase can't connect to some ODBC objects as external tables and will therefore not have a value in the TABLE_LOCATION column. Despite the absence of values in TABLE_LOCATION, the presence of one of these ODBC objects might make a database or schema non-empty.

Use sp_data_source_objects and sp_data_source_table_columns to discover external objects. These system stored procedures return the schema of tables that are available to be virtualized. Azure Data Studio uses these two stored procedures to support data virtualization. Use sp_data_source_table_columns to discover external table schemas represented in SQL Server data types.

External tables to MongoDB collections that contain arrays

To create external tables to MongoDB collections that contain arrays, you should use the Data Virtualization extension for Azure Data Studio to produce a CREATE EXTERNAL TABLE statement, based on the schema detected by the PolyBase ODBC Driver for MongoDB. The flattening actions are automatically performed by the driver. Alternatively, you can use sp_data_source_objects to detect the collection schema (columns) and manually create the external table. The sp_data_source_table_columns stored procedure also automatically performs the flattening via the PolyBase ODBC Driver for MongoDB driver. The Data Virtualization extension for Azure Data Studio and sp_data_source_table_columns use the same internal stored procedures to query the external schema.

Data source type specific remarks

  • Teradata

    Teradata system views don't use row-level security (RLS), and so users can see the existence of tables that they can't query.

  • MongoDB

    Some earlier versions of MongoDB restrict the ability to list all databases to admin-like users. Users without this permission might get auth errors trying to execute this procedure with a null @object_root_name.

  • Oracle

    Oracle synonyms aren't supported for usage with PolyBase.

Examples

SQL Server

The following example returns all databases, schemata, and tables/views

DECLARE @data_source SYSNAME = N'ExternalDataSourceName';
DECLARE @object_root_name NVARCHAR(MAX) = NULL;
DECLARE @max_search_depth INT = 3;

EXEC sp_data_source_objects @data_source,
    @object_root_name,
    @max_search_depth;
OBJECT_TYPE OBJECT_NAME OBJECT_LEAF_NAME TABLE_LOCATION
DATABASE "database" database NULL
SCHEMA "database"."dbo" dbo NULL
TABLE "database"."dbo"."customer" customer [database].[dbo].[customer]
TABLE "database"."dbo"."item" item [database].[dbo].[item]
TABLE "database"."dbo"."nation" nation [database].[dbo].[nation]

The following example returns all databases

DECLARE @data_source SYSNAME = N'ExternalDataSourceName';
DECLARE @object_root_name NVARCHAR(MAX) = NULL;

EXEC sp_data_source_objects @data_source, @object_root_name;
OBJECT_TYPE OBJECT_NAME OBJECT_LEAF_NAME TABLE_LOCATION
DATABASE UserDatabase UserDatabase NULL
DATABASE master master NULL
DATABASE msdb msdb NULL
DATABASE tempdb tempdb NULL
DATABASE database database NULL

The following example returns all schemata in a database

DECLARE @data_source SYSNAME = N'ExternalDataSourceName';
DECLARE @object_root_name NVARCHAR(MAX) = N'[database]';

EXEC sp_data_source_objects @data_source, @object_root_name;
OBJECT_TYPE OBJECT_NAME OBJECT_LEAF_NAME TABLE_LOCATION
SCHEMA "database"."dbo" dbo NULL
SCHEMA "database"."INFORMATION_SCHEMA" INFORMATION_SCHEMA NULL
SCHEMA "database"."sys" sys NULL

The following example returns all tables in schema

DECLARE @data_source SYSNAME = N'ExternalDataSourceName';
DECLARE @object_root_name NVARCHAR(MAX) = N'[database].[dbo]';

EXEC sp_data_source_objects @data_source, @object_root_name;
OBJECT_TYPE OBJECT_NAME OBJECT_LEAF_NAME TABLE_LOCATION
TABLE "database"."dbo"."customer" customer [database].[dbo].[customer]
TABLE "database"."dbo"."item" item [database].[dbo].[item]
TABLE "database"."dbo"."nation" nation [database].[dbo].[nation]
TABLE "database"."dbo"."orders" orders [database].[dbo].[orders]
TABLE "database"."dbo"."part" part [database].[dbo].[part]

Oracle

The following example returns the complete schemata and tables, functions, views, and etc.

DECLARE @data_source SYSNAME = N'ExternalDataSourceName';
DECLARE @object_root_name NVARCHAR(MAX) = N'[OracleObjectRoot]';
DECLARE @max_search_depth INT = 2;

EXEC sp_data_source_objects @data_source, @object_root_name, @max_search_depth;
OBJECT_TYPE OBJECT_NAME OBJECT_LEAF_NAME TABLE_LOCATION
VIEW "SYS"."ALL_SQLSET_STATEMENTS" ALL_SQLSET_STATEMENTS [ORACLEOBJECTROOT].[SYS].[ALL_SQLSET_STATEMENTS]
SYSTEM TABLE "SYS"."BOOTSTRAP$" BOOTSTRAP$ [ORACLEOBJECTROOT].[SYS].[BOOTSTRAP$]
SYNONYM "PUBLIC"."ALL_ALL_TABLES" ALL_ALL_TABLES NULL
SCHEMA "database" database NULL
TABLE "database"."customer" customer [ORACLEOBJECTROOT].[database].[customer]

Teradata

The following example returns all databases and tables, functions, views, and etc.

DECLARE @data_source SYSNAME = N'ExternalDataSourceName';
DECLARE @object_root_name NVARCHAR(MAX) = NULL;
DECLARE @max_search_depth INT = 2;

EXEC sp_data_source_objects @data_source, @object_root_name, @max_search_depth;
OBJECT_TYPE OBJECT_NAME OBJECT_LEAF_NAME TABLE_LOCATION
FUNCTION "SYSLIB"."ExtractRoles" ExtractRoles NULL
SYSTEM TABLE "DBC"."UDTCast" UDTCast [DBC].[UDTCast]
TYPE "SYSUDTLIB"."XML" XML NULL
DATABASE "database" database NULL
TABLE "database"."customer" customer [database].[customer]

Mongo DB

The following example returns all databases and tables.

DECLARE @data_source SYSNAME = N'ExternalDataSourceName';
DECLARE @object_root_name NVARCHAR(MAX) = NULL;
DECLARE @max_search_depth INT = 2;

EXEC sp_data_source_objects @data_source, @object_root_name, @max_search_depth;
OBJECT_TYPE OBJECT_NAME OBJECT_LEAF_NAME TABLE_LOCATION
DATABASE "database" database NULL
TABLE "database"."customer" customer [database].[customer]
TABLE "database"."item" item [database].[item]
TABLE "database"."nation" nation [database].[nation]
TABLE "database"."orders" orders [database].[orders]