Thread

1. Database corruption caused by long insert strings

   andrew@mycomport.com — 2000-05-03T05:47:15Z

   The system: Linux RedHat 6.2, running postgresql 6.5.3 (installed from the
   RH 6.2 RPM)
   
   The bug: attempts to insert large strings result in database
   corruption.  Not only does the attempted insert fail with a "too
   large" error, but the table is corrupted, and further accesses can cause
   the system to crash.
   
   I originally discovered this bug while accessing the database using Perl,
   but managed to replicate the problem using the command-line tools only.
   
   Test case:
   Create a database, connect to it using psql.
   
   testdb=>CREATE TABLE test (testcol text);
   CREATE
   testdb=>INSERT INTO test (testcol) values (<a really long string literal>);
   ERROR:  Tuple is too big: size 10584
   
   At this point, the database is corrupt.  "Vacuum"ing the database will
   detect and fix the corruption, but further queries without vacuuming may
   cause the system to crash (the postmaster daemon consumes all available
   CPU cycles).  I have not determined exactly how to trigger this.
   
   
   Thanks for an (otherwise) excellent product :-)
   
   Andrew Bishop
   
   
   

2. Re: Database corruption caused by long insert strings

   Peter Eisentraut <e99re41@docs.uu.se> — 2000-05-03T09:07:43Z

   On Wed, 3 May 2000 andrew@mycomport.com wrote:
   
   > The bug: attempts to insert large strings result in database
   > corruption.  Not only does the attempted insert fail with a "too
   > large" error, but the table is corrupted, and further accesses can cause
   > the system to crash.
   
   That's a known and fixed problem. Feel free to try our new product 7.0 --
   should be out on Monday last I heard.
   
   
   -- 
   Peter Eisentraut                  Sernanders väg 10:115
   peter_e@gmx.net                   75262 Uppsala
   http://yi.org/peter-e/            Sweden