sys.dm_exec_describe_first_result_set_for_object (Transact-SQL)

Artikel
02/28/2023

Applies to: SQL Server Azure SQL Database Azure SQL Managed Instance

This dynamic management function takes an @object_id as a parameter and describes the first result metadata for the module with that ID. The @object_id specified can be the ID of a Transact-SQL stored procedure or a Transact-SQL trigger. If it is the ID of any other object (such as a view, table, function, or CLR procedure), an error will be specified in the error columns of the result.

sys.dm_exec_describe_first_result_set_for_object has the same result set definition as sys.dm_exec_describe_first_result_set (Transact-SQL) and is similar to sp_describe_first_result_set (Transact-SQL).

Transact-SQL syntax conventions

Syntax

  
sys.dm_exec_describe_first_result_set_for_object   
    ( @object_id , @include_browse_information )

Arguments

@object_id
The @object_id of a Transact-SQL stored procedure or a Transact-SQL trigger. @object_id is type int.

@include_browse_information
@include_browse_information is type bit. If set to 1, each query is analyzed as if it has a FOR BROWSE option on the query. Returns additional key columns and source table information.

Table Returned

This common metadata is returned as a result set with one row for each column in the results metadata. Each row describes the type and nullability of the column in the format described in the following section. If the first statement does not exist for every control path, a result set with zero rows is returned.

Column name	Data type	Description
is_hidden	bit	Specifies whether the column is an extra column added for browsing information purposes that does not actually appear in the result set.
column_ordinal	int	Contains the ordinal position of the column in the result set. Position of the first column will be specified as 1.
name	sysname	Contains the name of the column if a name can be determined. Otherwise is NULL.
is_nullable	bit	Contains the value 1 if the column allows NULLs, 0 if the column does not allow NULLs, and 1 if it cannot be determined that the column allows NULLs.
system_type_id	int	Contains the system_type_id of the data type of the column as specified in sys.types. For CLR types, even though the system_type_name column will return NULL, this column will return the value 240.
system_type_name	nvarchar(256)	Contains the data type name. Includes arguments (such as length, precision, scale) specified for the data type of the column. If the data type is a user-defined alias type, the underlying system type is specified here. If it is a CLR user-defined type, NULL is returned in this column.
max_length	smallint	Maximum length (in bytes) of the column. -1 = Column data type is varchar(max), nvarchar(max), varbinary(max), or xml. For text columns, the max_length value will be 16 or the value set by sp_tableoption 'text in row'.
precision	tinyint	Precision of the column if numeric-based. Otherwise returns 0.
scale	tinyint	Scale of column if numeric-based. Otherwise returns 0.
collation_name	sysname	Name of the collation of the column if character-based. Otherwise returns NULL.
user_type_id	int	For CLR and alias types, contains the user_type_id of the data type of the column as specified in sys.types. Otherwise is NULL.
user_type_database	sysname	For CLR and alias types, contains the name of the database in which the type is defined. Otherwise is NULL.
user_type_schema	sysname	For CLR and alias types, contains the name of the schema in which the type is defined. Otherwise is NULL.
user_type_name	sysname	For CLR and alias types, contains the name of the type. Otherwise is NULL.
assembly_qualified_type_name	nvarchar(4000)	For CLR types, returns the name of the assembly and class defining the type. Otherwise is NULL.
xml_collection_id	int	Contains the xml_collection_id of the data type of the column as specified in sys.columns. This column will return NULL if the type returned is not associated with an XML schema collection.
xml_collection_database	sysname	Contains the database in which the XML schema collection associated with this type is defined. This column will return NULL if the type returned is not associated with an XML schema collection.
xml_collection_schema	sysname	Contains the schema in which the XML schema collection associated with this type is defined. This column will return NULL if the type returned is not associated with an XML schema collection.
xml_collection_name	sysname	Contains the name of the XML schema collection associated with this type. This column will return NULL if the type returned is not associated with an XML schema collection.
is_xml_document	bit	Returns 1 if the returned data type is XML and that type is guaranteed to be a complete XML document (including a root node), as opposed to an XML fragment). Otherwise returns 0.
is_case_sensitive	bit	Returns 1 if the column is of a case-sensitive string type and 0 if it is not.
is_fixed_length_clr_type	bit	Returns 1 if the column is of a fixed-length CLR type and 0 if it is not.
source_server	sysname	Name of the originating server returned by the column in this result (if it originates from a remote server). The name is given as it appears in sys.servers. Returns NULL if the column originates on the local server, or if it cannot be determined which server it originates on. Is only populated if browsing information is requested.
source_database	sysname	Name of the originating database returned by the column in this result. Returns NULL if the database cannot be determined. Is only populated if browsing information is requested.
source_schema	sysname	Name of the originating schema returned by the column in this result. Returns NULL if the schema cannot be determined. Is only populated if browsing information is requested.
source_table	sysname	Name of the originating table returned by the column in this result. Returns NULL if the table cannot be determined. Is only populated if browsing information is requested.
source_column	sysname	Name of the originating column returned by the column in this result. Returns NULL if the column cannot be determined. Is only populated if browsing information is requested.
is_identity_column	bit	Returns 1 if the column is an identity column and 0 if not. Returns NULL if it cannot be determined that the column is an identity column.
is_part_of_unique_key	bit	Returns 1 if the column is part of a unique index (including unique and primary constraint) and 0 if not. Returns NULL if it cannot be determined that the column is part of a unique index. Only populated if browsing information is requested.
is_updateable	bit	Returns 1 if the column is updateable and 0 if not. Returns NULL if it cannot be determined that the column is updateable.
is_computed_column	bit	Returns 1 if the column is a computed column and 0 if not. Returns NULL if it cannot be determined that the column is a computed column.
is_sparse_column_set	bit	Returns 1 if the column is a sparse column and 0 if not. Returns NULL if it cannot be determined that the column is a part of a sparse column set.
ordinal_in_order_by_list	smallint	Position of this column in ORDER BY list Returns NULL if the column does not appear in the ORDER BY list or if the ORDER BY list cannot be uniquely determined.
order_by_list_length	smallint	Length of the ORDER BY list. Returns NULL if there is no ORDER BY list or if the ORDER BY list cannot be uniquely determined. Note that this value will be the same for all rows returned by sp_describe_first_result_set.
order_by_is_descending	smallint NULL	If the ordinal_in_order_by_list is not NULL, the order_by_is_descending column reports the direction of the ORDER BY clause for this column. Otherwise it reports NULL.
error_number	int	Contains the error number returned by the function. Contains NULL if no error occurred in the column.
error_severity	int	Contains the severity returned by the function. Contains NULL if no error occurred in the column.
error_state	int	Contains the state message returned by the function. If no error occurred. the column will contain NULL.
error_message	nvarchar(4096)	Contains the message returned by the function. If no error occurred, the column will contain NULL.
error_type	int	Contains an integer representing the error being returned. Maps to error_type_desc. See the list under remarks.
error_type_desc	nvarchar(60)	Contains a short uppercase string representing the error being returned. Maps to error_type. See the list under remarks.

Remarks

This function uses the same algorithm as sp_describe_first_result_set. For more information, see sp_describe_first_result_set (Transact-SQL).

The following table lists the error types and their descriptions

error_type	error_type	Description
1	MISC	All errors that are not otherwise described.
2	SYNTAX	A syntax error occurred in the batch.
3	CONFLICTING_RESULTS	The result could not be determined because of a conflict between two possible first statements.
4	DYNAMIC_SQL	The result could not be determined because of dynamic SQL that could potentially return the first result.
5	CLR_PROCEDURE	The result could not be determined because a CLR stored procedure could potentially return the first result.
6	CLR_TRIGGER	The result could not be determined because a CLR trigger could potentially return the first result.
7	EXTENDED_PROCEDURE	The result could not be determined because an extended stored procedure could potentially return the first result.
8	UNDECLARED_PARAMETER	The result could not be determined because the data type of one or more of the result set's columns potentially depends on an undeclared parameter.
9	RECURSION	The result could not be determined because the batch contains a recursive statement.
10	TEMPORARY_TABLE	The result could not be determined because the batch contains a temporary table and is not supported by sp_describe_first_result_set .
11	UNSUPPORTED_STATEMENT	The result could not be determined because the batch contains a statement that is not supported by sp_describe_first_result_set (e.g., FETCH, REVERT etc.).
12	OBJECT_ID_NOT_SUPPORTED	The @object_id passed to the function is not supported (i.e. not a stored procedure)
13	OBJECT_ID_DOES_NOT_EXIST	The @object_id passed to the function was not found in the system catalog.

Permissions

Requires permission to execute the @tsql argument.

Examples

A. Returning metadata with and without browse information

The following example creates a stored procedure named TestProc2 that returns two result sets. Then the example demonstrates that sys.dm_exec_describe_first_result_set returns information about the first result set in the procedure, with and without the browse information.

CREATE PROC TestProc2  
AS  
SELECT object_id, name FROM sys.objects ;  
SELECT name, schema_id, create_date FROM sys.objects ;  
GO  
  
SELECT * FROM sys.dm_exec_describe_first_result_set_for_object(OBJECT_ID('TestProc2'), 0) ;  
SELECT * FROM sys.dm_exec_describe_first_result_set_for_object(OBJECT_ID('TestProc2'), 1) ;  
GO

B. Combining the sys.dm_exec_describe_first_result_set_for_object function and a table or view

The following example uses both the sys.procedures system catalog view and the sys.dm_exec_describe_first_result_set_for_object function to display metadata for the result sets of all stored procedures in the AdventureWorks2022 database.

USE AdventureWorks2022;  
GO  
  
SELECT p.name, r.*   
FROM sys.procedures AS p  
CROSS APPLY sys.dm_exec_describe_first_result_set_for_object(p.object_id, 0) AS r;  
GO

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