опубликован 07-01-2002 13:04 MSK            

#include <oracl.h>
#include <iostream.h>
#include <fstream.h>

// Example for OBlob::Write

int main()
{
//Initialize oo4o, connect, execute sql
OStartup();
ODatabase odb("ExampleDB", "scott", "tiger");
ODynaset odyn(odb, "SELECT * FROM PART");
if (!odyn.IsOpen())
{
cout <<"Connect Error: "<<odb.GetErrorText()<<endl;
cout <<"SQL Error: "<<odyn.GetErrorText()<<endl;
return 1;
}

//prior to modifying a LOB for the first time,
//we must first insert an Empty LOB and then commit
OValue val;
val.SetEmpty();
odyn.AddNewRecord();
oresult ores = odyn.SetFieldValue((const char *)"PART_IMAGE", val);
ores = odyn.Update();
OBlob oblob;
odyn.StartEdit();
odyn.GetFieldValue("PART_IMAGE", &oblob);
unsigned char *buffer = 0;
try
{
// calculate an optimum buffersize of approximately 32k bytes
unsigned long optchunk = oblob.GetOptimumChunkSize();
unsigned int bufsize = ((int)(32768/optchunk)) *optchunk;
buffer = (unsigned char *)malloc(bufsize);
//open file and get file size
fstream fs;
fs.open("C:\\Oracle\\Ora81\\Oo4o\\Cpp\\Workbook\\Lob\\partimage.dat", ios::in);
fs.setmode(filebuf::binary);
fs.seekg(0, ios::end);
unsigned long filesize = fs.tellg();
fs.seekg(0, ios::beg);

unsigned long totalwritten = 0;
unsigned long amtread = 0;
int piecetype = OLOB_FIRST_PIECE;

//By taking advantage of streaming we get the best performance
//and we don't need to allocate a huge buffer.
if (filesize <= bufsize)
piecetype = OLOB_ONE_PIECE;
else
oblob.EnableStreaming(filesize);
while(totalwritten != filesize)
{
fs.read(buffer, bufsize);
amtread = fs.gcount();
oblob.Write(buffer, amtread, piecetype);
totalwritten = totalwritten + amtread;

if ((filesize - totalwritten)<=bufsize)
piecetype = OLOB_LAST_PIECE;
else
piecetype = OLOB_NEXT_PIECE;
}

oblob.DisableStreaming();
ores = odyn.Update();
fs.close();
}
catch(OException E)
{
cout<<E.GetFailedMethodName()<< " Error: "<<E.GetErrorText()<<endl;
}
if (buffer)
free(buffer);

OShutdown();
return 0;
}

опубликован 09-01-2002 23:59 MSK            

помоему полюбому проще админить *них системы.