Why can I use an alias for group by and order by and not for having? I am just wondering if there is some barrier to it being implemented, or if it just hasn't been.
select table_schema || '.' || table_name AS schema_qualified_table_name, count( column_name ) as column_count from information_schema.columns group by schema_qualified_table_name having count( column_name ) > 50 /* this works, but trying column_count > 50 does not */ order by column_count desc;
