[freetds] Querying from multiple threads - SEGMENTATION FAULT

Sohaib Rasheed sohaibrasheed at yahoo.com
Fri Dec 30 00:28:49 EST 2005


 I am facing a problem using TDS. The problem occurs only when using  multiple threads to access SQL Server 2000. The current scenerio is  that whenever I need to query database in a thread, the thread opens  the db (dbopen), executes the query, checks the results etc and in the  end closes the db connection (dbclose). The problem arrises when while  a thread is processing the results, the other thread calls dbopen to  open a connection with same LOGINREC. Sometimes it even occurs in other  states as well and results in segmenation fault. I used another  approach to solve this problem and that was to create a connection pool  and give a free connection to a thread and calling dbcancel before  binding parameters and executing the query. Everything worked fine  until a special case arrived. If I bind a varchar parameter will NULL  value (NULL acceptable in SP) and specify maximum length = -1 and  Length = -1. the bind function fails but now even the valid q uries  which were running
 fine wont run on the same DBPROCESS. I cannot call  dbclose and then dbopen again bcuz of the reason mentioned above. Can  anybody help me on this? And can anybody tell me why this happens and  how can I avoid it? If I check for the values of length and max length  while binding the parameter myself then can anybody provide me with the  list that can cause the same problem?

		
---------------------------------
Yahoo! Shopping
 Find Great Deals on Holiday Gifts at Yahoo! Shopping 



More information about the FreeTDS mailing list