In MS SQL Server 2005, how can I extract statistical information about NULL fraction (or NULL count) for a given column?
Same information is available in Oracle and PostgreSQL, and I heard that MS SQL also has statistics, but I don't know where to find it. Google didn't help much.
I hope I will hear something like
SELECT null_frac FROM pg_stats WHERE tablename='mytab' and attname='mycol'; /* PostgreSQL, stats gathered by ANALYZE */
SELECT nullcnt FROM custom_stats_table WHERE tabname='MYTAB' and colname='MYCOL'; /* Oracle, stats gathered by dbms_stats.get_column_stats */
I'm not asking how to compute these values myself - I know how to do it. I need these stats for several thousands of columns, and computing this would take very long on the database that I'm working on. I need approximations, and they should be somewhere in the server - they are needed anyway for cost-based optimizer.