Calls the CREATE STATISTICS statement to create single-column statistics on columns that are not already the first column in a statistics object. Creating single-column statistics increases the number of histograms, which can improve cardinality estimates, query plans, and query performance. The first column of a statistics object has a histogram; other columns do not have a histogram.
sp_createstats is useful for applications such as benchmarking when query execution times are critical and cannot wait for the query optimizer to generate single-column statistics. In most cases, it is not necessary to use sp_createstats; the query optimizer generates single-column statistics as necessary to improve query plans when the AUTO_CREATE_STATISTICS option is on.
For more information about statistics, see Statistics. For more information about generating single-column statistics, see the AUTO_CREATE_STATISTICS option in ALTER DATABASE SET Options (Transact-SQL).
sp_createstats does not create or update statistics on columns that are the first column in an existing statistics object; This includes the first column of statistics created for indexes, columns with single-column statistics generated with AUTO_CREATE_STATISTICS option, and the first column of statistics created with the CREATE STATISTICS statement. sp_createstats does not create statistics on the first columns of disabled indexes unless that column is used in another enabled index. sp_createstats does not create statistics on tables with a disabled clustered index.
When the table contains a column set, sp_createstats does not create statistics on sparse columns. For more information about column sets and sparse columns, see Use Column Sets and Use Sparse Columns.
A. Create single-column statistics on all eligible columns
The following example creates single-column statistics on all eligible columns in the current database.
EXEC sp_createstats; GO
B. Create single-column statistics on all eligible index columns
The following example creates single-column statistics on all eligible columns that are already in an index and are not the first column in the index.
EXEC sp_createstats 'indexonly'; GO