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From: [EMAIL PROTECTED]
To: [EMAIL PROTECTED]
Subject: MySQL strange error: lost connection during query

 >Description:
   When 2 concurrent processes access the database 'sometimes' MySQL 
reports this error to both processes at the same time. It happens very 
rarely and about 10 seconds later they continue with its normal work. 
When we increase the number of processes accessing the database this 
happens more often.
   Following queries after this error return 'MySQL server has gone 
away'. The processes access the database stored at localhost.
   It is possible that the tables involved in the queries could get 
corrupted after this error. Then, database must be repaired before any 
successive inserts in the table.

 >How-To-Repeat:

void insercion(MYSQL mysql_h1, int orden)
{
  int i=1;

  if( mysql_query(&mysql_h1, "insert into conexiones values ('', \
'a5sbue123', 'f3089047', 'fassion', '', NULL, 'P', 0)") )
    
   do {
     printf("%d ERROR %s, n.try %d\n", orden,
       mysql_error(&mysql_h1), ++i );
     sleep( rand() % 5 +1 );

   } while( mysql_query(&mysql_h1, "insert into conexiones values ('', \
'a5sbue123', 'f3089047', 'fassion', '', NULL, 'P', 0)") );

  else
   printf("%d Correct!\n", orden);
 
}

   This is the possible fix in the user code, retrying some times and 
about a random time (in order to avoid another concurrent error). But it 
doesn't work. Sometimes reports: 'Database not selected' maybe because 
after a bad query the connection to the database has been lost?
   I have tested this code in a linux machine with 15 simultaneus 
processes and it doesn't happen at all. Could be a problem with the 
architecture?

 >Fix:
   Unknown fix

 >Submitter-Id:    Zeus Gomez Marmolejo
 >Originator:   
 >Organization: Facultat d'Informatica de Barcelona [UPC]
<organization of PR author (multiple lines)>
 >MySQL support: none
 >Synopsis:    MySQL error report
 >Severity:    serious
 >Priority:    medium
 >Category:    mysql
 >Class:        sw-bug
 >Release:    mysql-3.23.38 (Official MySQL binary)
 >Environment:
   <machine, os, target, libraries (multiple lines)>
System: OSF1 merlin.fib.upc.es V5.1 732 alpha
Machine: alpha
Some paths:  /usr/bin/perl /usr/bin/make /usr/local/bin/gmake 
/usr/local/bin/gcc /usr/bin/cc
GCC: Reading specs from 
/usr/local/lib/gcc-lib/alpha-dec-osf4.0e/egcs-2.91.66/specs
gcc version egcs-2.91.66 19990314 (egcs-1.1.2 release)
Compilation info: CC='cc -pthread'  CFLAGS='-O4 -ansi_alias -ansi_args 
-fast -inline speed -speculate all'  CXX='cxx -pthread'  CXXFLAGS='-O4 
-ansi_alias -fast -inline speed -speculate all -noexceptions -nortti'  
LDFLAGS=''
LIBC:
lrwxrwxrwx   1 root     system        17 Jun 14 13:04 /lib/libc.a -> 
../ccs/lib/libc.a
lrwxrwxrwx   1 root     system        17 Jun 14 13:04 /usr/lib/libc.a -> 
../ccs/lib/libc.a
Configure command: ./configure  --prefix=/usr/local/mysql 
'--with-comment=Official MySQL binary' --with-extra-charsets=complex 
--with-server-suffix= --with-prefix=/usr/local/mysql 
--with-mysqld-ldflags=-all-static --disable-shared 
'--with-named-thread-libs=-lpthread -lmach -lexc -lc' --disable-shared
Perl: This is perl, version 5.005_03 built for alpha-dec_osf


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