We add statistics on the columns that don't have statistics in order to boost query performance. UPDATE_STATISTICS Updates query optimization statistics on a table or indexed view. By default, the query optimizer already updates statistics as necessary to improve the query plan but in some cases you can improve query performance by using UPDATE_STATISTICS or the stored procedure sp_updatestats to update statistics more frequently than the default updates.
UPDATE_STATISTICS command is basically used when a large processing of data has occurred. If a large amount of deletions any modification or Bulk Copy into the tables has occurred, it has to update the indexes to take these changes into account. UPDATE_STATISTICS updates the indexes on these tables accordingly.
Here is T-SQL Command:
1. Updating All Statistics with sp_updatestats
Update all statistics on a table
UPDATE STATISTICS TableName
Update the statistics for an index
UPDATE STATISTICS TableName, IndexName
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