Обсуждение: C++ Builder (Delphi), ODBC and large objects
I have problem using large objects with C++ Builder. When client side writes to the database psqlodbc.log reports that 0-value is inserted into large-object field. When client try to read data from the psqlodbc.log reports "Couldnt open large object for reading" I've asked this question to the mailin list already, but nobody answers. Perhaps because I wrote too long request. Now I ask to answer several simple questions: 1 Does anybody use large objects with C++ Builder (Delphi), BDE, ODBC, PostgreSQL? 2 Does anybody know (or suspect) who (C++ Builder (Delphi), BDE, ODBC or PostgreSQL) is responcible for the error? 3 Can anybody give me patch OR algorithm OR idea OR source for info OR hint to solve the problem. Thank you, Mikhail.
angg wrote: > I have problem using large objects with C++ Builder. > When client side writes to the database psqlodbc.log reports that 0-value is > inserted into large-object field. > When client try to read data from the psqlodbc.log reports "Couldnt open > large object for reading" > I've asked this question to the mailin list already, but nobody answers. I must confess, this is the first I email on ODBC large objects I recall seeing in a while. > Perhaps because I wrote too long request. Now I ask to answer several simple > questions: > 1 Does anybody use large objects with C++ Builder (Delphi), BDE, ODBC, > PostgreSQL? Yes, occasionally - without any problem. > 2 Does anybody know (or suspect) who (C++ Builder (Delphi), BDE, ODBC or > PostgreSQL) is responcible for the error? No. > 3 Can anybody give me patch OR algorithm OR idea OR source for info OR hint > to solve the problem. Have you seen http://www.insightdist.com/psqlodbc/psqlodbc_faq.html#largeobjects There is also a contribution to the 6.4 source tree which sets up triggers to remove orphaned large objects.
On Tue, 20 Oct 1998, David Hartwig wrote: > > > angg wrote: > > > I have problem using large objects with C++ Builder. > > When client side writes to the database psqlodbc.log reports that 0-value is > > inserted into large-object field. > > When client try to read data from the psqlodbc.log reports "Couldnt open > > large object for reading" > > I've asked this question to the mailin list already, but nobody answers. > > I must confess, this is the first I email on ODBC large objects I recall seeing > in a while. > > > Perhaps because I wrote too long request. Now I ask to answer several simple > > questions: > > 1 Does anybody use large objects with C++ Builder (Delphi), BDE, ODBC, > > PostgreSQL? > > Yes, occasionally - without any problem. Do you mean BLOB+ODBC+BDE+Delphi worked for you with no problems? And you accessed BLOBs using TTable or TQuery in Delphi? What were your ODBC and BDE settings? Andrzej
Andrzej Szydlo wrote: > On Tue, 20 Oct 1998, David Hartwig wrote: > > > > > > > angg wrote: > > > > > I have problem using large objects with C++ Builder. > > > When client side writes to the database psqlodbc.log reports that 0-value is > > > inserted into large-object field. > > > When client try to read data from the psqlodbc.log reports "Couldnt open > > > large object for reading" > > > I've asked this question to the mailin list already, but nobody answers. > > > > I must confess, this is the first I email on ODBC large objects I recall seeing > > in a while. > > > > > Perhaps because I wrote too long request. Now I ask to answer several simple > > > questions: > > > 1 Does anybody use large objects with C++ Builder (Delphi), BDE, ODBC, > > > PostgreSQL? > > > > Yes, occasionally - without any problem. > > Do you mean BLOB+ODBC+ worked for you with no problems? > And you accessed BLOBs using TTable or TQuery in Delphi? What were your > ODBC and BDE settings? > > Andrzej Apologies. There is a problem with BLOG+BDE+Delphi. Other applications that I have used don't have any problems. Byron is looking at it now.
On Tue, 20 Oct 1998, David Hartwig wrote: > > > Andrzej Szydlo wrote: > > > On Tue, 20 Oct 1998, David Hartwig wrote: > > [...] > > > > Do you mean BLOB+ODBC+ worked for you with no problems? > > And you accessed BLOBs using TTable or TQuery in Delphi? What were your > > ODBC and BDE settings? > > > > Apologies. There is a problem with BLOG+BDE+Delphi. Other applications that I > have used don't have any problems. Byron is looking at it now. We've found out by now that Delphi has no problems getting and putting BLOBs using direct BDE API calls. The problem seems to be in the Delphi components library, but there's no source available to trace and correct it. Let me know if you think we might be helpful in this matter in any way. Andrzej
angg wrote: > I have problem using large objects with C++ Builder. > When client side writes to the database psqlodbc.log reports that 0-value is > inserted into large-object field. > When client try to read data from the psqlodbc.log reports "Couldnt open > large object for reading" > I've asked this question to the mailin list already, but nobody answers. > Perhaps because I wrote too long request. Now I ask to answer several simple > questions: > 1 Does anybody use large objects with C++ Builder (Delphi), BDE, ODBC, > PostgreSQL? > 2 Does anybody know (or suspect) who (C++ Builder (Delphi), BDE, ODBC or > PostgreSQL) is responcible for the error? > 3 Can anybody give me patch OR algorithm OR idea OR source for info OR hint > to solve the problem. > Thank you, Mikhail. Please send me the psqlodbc.log files showing both the "0-value" error and the "couldn't open large object for reading". Also, send the odbc trace log files (sql.log) as well showing the results of both the read and write attempts. Make sure the log file is clean before you begin. Byron