The following bug has been logged on the website:

Bug reference:      7853
Logged by:          James Skaggs
Email address:      jim...@seagate.com
PostgreSQL version: 8.4.14
Operating system:   RHEL6
Description:        

After "analyze verbose", the table shows 158 million rows. A select count(1)
yields 13.8 million rows.

INFO:  analyzing "public.stream_file"
INFO:  "stream_file": scanned 30000 of 2123642 pages, containing 184517 live
rows and 2115512 dead rows; 30000 rows in sample, 158702435 estimated total
rows

Here are the table statistics.

Sequential Scans        81853   
Sequential Tuples Read  578848425234    
Index Scans     1976513672      
Index Tuples Fetched    2183339860      
Tuples Inserted 65122575        
Tuples Updated  308883671       
Tuples Deleted  51238760        
Tuples HOT Updated      2242897 
Live Tuples     163981972       
Dead Tuples     7056493 
Heap Blocks Read        43483331819     
Heap Blocks Hit 43121456487     
Index Blocks Read       134539277       
Index Blocks Hit        13606451182     
Toast Blocks Read               
Toast Blocks Hit                
Toast Index Blocks Read         
Toast Index Blocks Hit          
Last Vacuum     2013-02-04 10:06:44.058743-07   
Last Autovacuum 2013-02-04 16:11:34.289823-07   
Last Analyze    2013-02-04 14:22:27.848547-07   
Last Autoanalyze        2013-02-01 17:37:29.855553-07   
Table Size      17 GB   
Toast Table Size        none    
Indexes Size    34 GB
Query returned successfully with no result in 4094 ms.


Bad statistics led to a bad plan.  We will cluster the table today to see if
that fixes it, but I think statistics should be correct, regardless of the
state of a table.  BTW, Coverity product requries 8.x, and we'll upgrade to
8.4.15 today. Didn't see anything about better statistics in the 8.4.15
changelog.



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