C++ Programming Code Examples
C++ > Algorithms Code Examples
Accessing SQL Server from C++
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/* Accessing SQL Server from C++ */
#define DBNTWIN32
#include <stdio.h>
#include <windows.h>
#include <sqlfront.h>
#include <sqldb.h>
// Forward declarations of the error handler and message handler.
int err_handler(PDBPROCESS, INT, INT, INT, LPCSTR, LPCSTR);
int msg_handler(PDBPROCESS, DBINT, INT, INT, LPCSTR, LPCSTR,
LPCSTR, DBUSMALLINT);
main()
{
PDBPROCESS dbproc; // The connection with SQL Server.
PLOGINREC login; // The login information.
DBCHAR name[100];
DBCHAR city[100];
// Install user-supplied error- and message-handling functions.
dberrhandle (err_handler);
dbmsghandle (msg_handler);
// Initialize DB-Library.
dbinit ();
// Get a LOGINREC.
login = dblogin ();
DBSETLUSER (login, "my_login");
DBSETLPWD (login, "my_password");
DBSETLAPP (login, "example");
// Get a DBPROCESS structure for communication with SQL Server.
dbproc = dbopen (login, "my_server");
// Retrieve some columns from the authors table in the
// pubs database.
// First, put the command into the command buffer.
dbcmd (dbproc, "SELECT au_lname, city FROM pubs..authors");
dbcmd (dbproc, " WHERE state = 'CA' ");
// Send the command to SQL Server and start execution.
dbsqlexec (dbproc);
// Process the results.
if (dbresults (dbproc) == SUCCEED)
{
// Bind column to program variables.
dbbind (dbproc, 1, NTBSTRINGBIND, 0, name);
dbbind (dbproc, 2, NTBSTRINGBIND, 0, city);
// Retrieve and print the result rows.
while (dbnextrow (dbproc) != NO_MORE_ROWS)
{
printf ("%s from %s\n", name, city);
}
}
// Close the connection to SQL Server.
dbexit ();
return (0);
}
int err_handler (PDBPROCESS dbproc, INT severity,
INT dberr, INT oserr, LPCSTR dberrstr, LPCSTR oserrstr)
{
printf ("DB-Library Error %i: %s\n", dberr, dberrstr);
if (oserr != DBNOERR)
{
printf ("Operating System Error %i: %s\n", oserr, oserrstr);
}
return (INT_CANCEL);
}
int msg_handler (PDBPROCESS dbproc, DBINT msgno, INT msgstate,
INT severity, LPCSTR msgtext, LPCSTR server,
LPCSTR procedure, DBUSMALLINT line)
{
printf ("SQL Server Message %ld: %s\n", msgno, msgtext);
return (0);
}
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