Loading clob data/Migrating from Informix

Question

Hi,
I wanted to understand a way to insert clob data into the database. I see that you have ways of retrieving and displaying the clobs/blobs in your demo programs. But, how do we go about inserting clob data into a column? And especially, How to accomplish this when the data is stored in the form of a file?
We're in the process of migrating from Informix to Oracle and Informix has this way of storing the clob contents into .EMB files. Moreover, there is no one-to-one correspondence between each clob column and an .EMB file. Informix just knows how to load them up when you use FILETOCLOB(). In similar lines, do we have a way to load clob data from files to start with. And would be glad to get some intricacies on achieving the migration of data from Informix database.
Please send me pointers to docs and procedures, if available.
Thanks for your time
Chandra M.

Answer 1

You can see this sample:
/******* schema ********
create table city
(id integer ,
cimg blob DEFAULT NULL
#include <iostream>
#include <fstream>
#include <occi.h>
using namespace oracle::occi;
using namespace std;
#define BUFSIZE 8192
Environment *env;
Connection *conn;
int res=0;
unsigned int offsetw=1;
unsigned char readbuf[BUFSIZE];
main()
try {
env = Environment::createEnvironment();
conn = env->createConnection("scott","tiger");
catch(SQLException &x)
cout << "Error :" << x.what() <<"\n";
return 1;
try
ifstream infile ("bangalore.jpg", ios::binary);
if (!infile.is_open()) cout << "could not open bangalore.jpg\n";
else
Statement *stmt = conn->createStatement();
stmt->setSQL( "INSERT INTO city VALUES(1, EMPTY_BLOB())");
stmt->execute();
stmt->setSQL("SELECT cimg from city where id = 1");
stmt->execute();
ResultSet *rs= stmt->getResultSet();
rs->next();
Blob blob(conn);
blob = rs->getBlob(1);
blob.open();
do
infile.read((char *)readbuf,BUFSIZE);
res=infile.gcount();
if (!res) break;
blob.writeChunk(res,readbuf, BUFSIZE, offsetw);
offsetw+=res;
} while (1);
infile.close();
blob.close();
conn->commit();
catch(SQLException &x)
cout << "Error :" << x.what() <<"\n";
try{
env->terminateConnection(conn);
Environment::terminateEnvironment(env);
catch(SQLException &x)
cout << "Error :" << x.what() <<"\n";
} /* end of main */