To add statistics for the price column in the titles table, enter:
update statistics titles (price)
To specify the number of histogram steps for a column, use:
update statistics titles (price) using 50 values
This command adds a histogram for the titles.pub_id column and generates density values for the prefix subsets pub_id; pub_id, pubdate; and pub_id, pubdate, title_id:
update statistics titles(pub_id, pubdate, title_id)
However, this command does not create a histogram on pubdate
and title_id
,
since a separate update statistics command is
needed for every column for which a histogram is desired.
Running update statistics with a table name updates histograms and densities for leading columns for indexes only; it does not update the statistics for unindexed columns. To maintain these statistics, run update statistics and specify the column name, or run update all statistics.