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From:Etienne Hirt Date:April 11 2006 6:57pm
Subject:Error when fetching data of a Union query with Version 2.1.0
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 While fetching data from a union query as shown in the code fragment 
below I get the following error when fetching the data from the second 
part which is only one row. The same behaviour is found when using a 
similar query also limited to one row:
Untreated Exception at 0x102163d4 (msvcr71d.dll) in analysis.exe: 
0xC0000005: AccessError-Writeposition 0x20333535.

The data access crashes when I either want to assign a row to the SSQL 
struct  dbEvent or when  accessing to the data with row["name"] .

Is there another option to access the data?

Etienne

//set up query
   sprintf(queryString, "(Select * from event where Measurements_ID = 
'%.4d-%.2d-%.2d %.2d:%.2d:%.2d' and Event_DataFilePos >= %d and 
Event_DataFilePos <= %d order by Event_DataFilePos)",
            m_startYear, m_startMonth, m_startDay, m_startHour, 
m_startMinute, m_startSecond, dataFileFirstPosition, dataFileLastPosition);
        sprintf(queryString,"%s UNION DISTINCT (Select * from event 
where Measurements_ID = '%.4d-%.2d-%.2d %.2d:%.2d:%.2d' and 
Event_DataFilePos >= %d and Event_Type = 'p' order by Event_DataFilePos 
ASC LIMIT 1)",
            queryString, m_startYear, m_startMonth, m_startDay, 
m_startHour, m_startMinute, m_startSecond, dataFileLastPosition, 
dataFileLastPosition);

        resUse = query.use(queryString);

//Access data from query
        while (row = resUse.fetch_row())
        {
            dbEvent = row;
            //event[counter].dataFilePosition = row["Event_DataFilePos"];



-- 
++++++++++++++++++++++++++++++++++++++++++++++
Dr. Etienne Hirt          Art of Technology
Director R&D              www.art-of-technology.ch
Technoparkstrasse 1       Ph: +41-43-311 77 02
8005 Zurich               Sw: +41-43-311 77 00
Switzerland
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Thread
Error when fetching data of a Union query with Version 2.1.0Etienne Hirt11 Apr
  • Re: Error when fetching data of a Union query with Version 2.1.0Warren Young13 Apr
    • Re: Error when fetching data of a Union query with Version 2.1.0Etienne Hirt14 Apr
      • Re: Error when fetching data of a Union query with Version 2.1.0Warren Young15 Apr