Muokkaa

Jaa

sp_statistics (Transact-SQL)

  • Artikkeli

Applies to: SQL Server Azure SQL Database Azure SQL Managed Instance Azure Synapse Analytics Analytics Platform System (PDW)

Returns a list of all indexes and statistics on a specified table or indexed view.

Transact-SQL syntax conventions

Syntax

sp_statistics
    [ @table_name = ] N'table_name'
    [ , [ @table_owner = ] N'table_owner' ]
    [ , [ @table_qualifier = ] N'table_qualifier' ]
    [ , [ @index_name = ] N'index_name' ]
    [ , [ @is_unique = ] 'is_unique' ]
    [ , [ @accuracy = ] 'accuracy' ]
[ ; ]

Note

This syntax is not supported by serverless SQL pool in Azure Synapse Analytics.

Arguments

[ @table_name = ] N'table_name'

Specifies the table used to return catalog information. @table_name is sysname, with no default. Wildcard pattern matching isn't supported.

[ @table_owner = ] N'table_owner'

The name of the table owner of the table used to return catalog information. @table_owner is sysname, with a default of NULL. Wildcard pattern matching isn't supported. If owner isn't specified, the default table visibility rules of the underlying database management system (DBMS) apply.

In SQL Server, if the current user owns a table with the specified name, the indexes of that table are returned. If owner isn't specified and the current user doesn't own a table with the specified name, this procedure looks for a table with the specified name owned by the database owner. If one exists, the indexes of that table are returned.

[ @table_qualifier = ] N'table_qualifier'

The name of the table qualifier. @table_qualifier is sysname, with a default of NULL. Various DBMS products support three-part naming for tables (<qualifier>.<owner>.<name>). In SQL Server, this parameter represents the database name. In some products, it represents the server name of the table's database environment.

[ @index_name = ] N'index_name'

The index name. @index_name is sysname, with a default of %. Wildcard pattern matching is supported.

[ @is_unique = ] 'is_unique'

Whether only unique indexes (if Y) are to be returned. @is_unique is char(1), with a default of empty string.

[ @accuracy = ] 'accuracy'

The level of cardinality and page accuracy for statistics. @accuracy is char(1), with a default of Q. Specify E to make sure that statistics are updated so that cardinality and pages are accurate.

  • E (SQL_ENSURE) asks the driver to unconditionally retrieve the statistics.

  • Q (SQL_QUICK) asks the driver to retrieve the cardinality and pages, only if they're readily available from the server. In this case, the driver doesn't ensure that the values are current. Applications that are written to the Open Group standard always get SQL_QUICK behavior from ODBC 3.x-compliant drivers.

Result set

Column name Data type Description
TABLE_QUALIFIER sysname Table qualifier name. This column can be NULL.
TABLE_OWNER sysname Table owner name. This column always returns a value.
TABLE_NAME sysname Table name. This column always returns a value.
NON_UNIQUE smallint Not nullable.

0 = Unique
1 = Not unique
INDEX_QUALIFIER sysname Index owner name. Some DBMS products allow for users other than the table owner to create indexes. In SQL Server, this column is always the same as TABLE_NAME.
INDEX_NAME sysname The name of the index. This column always returns a value.
TYPE smallint This column always returns a value:

0 = Statistics for a table
1 = Clustered
2 = Hashed
3 = Nonclustered
SEQ_IN_INDEX smallint Position of the column within the index.
COLUMN_NAME sysname Column name for each column of the TABLE_NAME returned. This column always returns a value.
COLLATION char(1) Order used in collation. Can be:

A = Ascending
D = Descending
NULL = Not applicable
CARDINALITY int Number of rows in the table or unique values in the index.
PAGES int Number of pages to store the index or table.
FILTER_CONDITION varchar(128) SQL Server doesn't return a value.

Return code values

None.

Remarks

The indexes in the result set appear in ascending order by the columns NON_UNIQUE, TYPE, INDEX_NAME, and SEQ_IN_INDEX.

The index type clustered refers to an index in which table data is stored in the order of the index. This value corresponds to SQL Server clustered indexes.

The index type Hashed accepts exact match or range searches, but pattern matching searches don't use the index.

The sp_statistics system stored procedure is equivalent to SQLStatistics in ODBC. The results returned are ordered by NON_UNIQUE, TYPE, INDEX_QUALIFIER, INDEX_NAME, and SEQ_IN_INDEX. For more information, see the ODBC Reference.

Permissions

Requires SELECT permission on the schema.

Example: Azure Synapse Analytics and Analytics Platform System (PDW)

The following example returns information about the DimEmployee table from the AdventureWorks sample database.

EXEC sp_statistics DimEmployee;

Related content