Connect C ++ to Oracle

I have just learned C ++, and I feel like I have learned something faster!

The following is the code of a small program connecting to Oracle using ADO ......

First, configure Oracle, find the Oracle \ network \ ADMIN \ tnsnames. ora file in the Oracle installation path, and configure the connection configuration.

[Plain]
BOSS =
(DESCRIPTION =
(ADDRESS_LIST =
(ADDRESS = (PROTOCOL = TCP) (HOST = xx. xx) (PORT = 1521 ))
)
(CONNECT_DATA =
(SERVICE_NAME = boss)
)
)

BOSS =
(DESCRIPTION =
(ADDRESS_LIST =
(ADDRESS = (PROTOCOL = TCP) (HOST = xx. xx) (PORT = 1521 ))
)
(CONNECT_DATA =
(SERVICE_NAME = boss)
)
) Create a new header file named CDBOperation. h:

[Cpp]
# Pragma once
# Import "c: \ program files \ common files \ system \ ado \ msado15.dll" no_namespace rename ("EOF", "adoEOF ")
Class CDBOperation
{
Public:
// Initialize the objects required for database operations
CDBOperation (void );
~ CDBOperation (void );
 
// Connect to the database
Bool ConnToDB (char * ConnectionString, char * UserID, char * Password );
 
// Database operation functions
// Query operation deletion and Addition
_ RecordsetPtr ExecuteWithResSQL (const char *);
 
Private:
Void PrintErrorInfo (_ com_error &);
 
Private:
// Initialize database connections, commands, and Record Sets
_ ConnectionPtr CreateConnPtr ();
_ CommandPtr createcommp tr ();
_ RecordsetPtr CreateRecsetPtr ();
 
Private:
// Connection and command operation objects required for database connection
_ ConnectionPtr m_pConnection;
_ CommandPtr m_pCommand;
};

# Pragma once
# Import "c: \ program files \ common files \ system \ ado \ msado15.dll" no_namespace rename ("EOF", "adoEOF ")
Class CDBOperation
{
Public:
// Initialize the objects required for database operations
CDBOperation (void );
~ CDBOperation (void );

// Connect to the database
Bool ConnToDB (char * ConnectionString, char * UserID, char * Password );

// Database operation functions
// Query operation deletion and Addition
_ RecordsetPtr ExecuteWithResSQL (const char *);

Private:
Void PrintErrorInfo (_ com_error &);

Private:
// Initialize database connections, commands, and Record Sets
_ ConnectionPtr CreateConnPtr ();
_ CommandPtr createcommp tr ();
_ RecordsetPtr CreateRecsetPtr ();

Private:
// Connection and command operation objects required for database connection
_ ConnectionPtr m_pConnection;
_ CommandPtr m_pCommand;
}; Create a c ++ source file named CDBOperation. cpp:
[Cpp]
# Include "stdafx. h"
# Include "DBOperation. h"
CDBOperation: CDBOperation (void)
{
CoInitialize (NULL );
M_pConnection = CreateConnPtr ();
M_pCommand = createcomatrix tr ();
}
CDBOperation ::~ CDBOperation (void)
{
M_pConnection-> Close ();
}
Bool CDBOperation: ConnToDB (char * ConnectionString, char * UserID, char * Password)
{
If (NULL = m_pConnection)
{
Printf ("Failed to create connection \ n ");
Return false;
}
Try
{
HRESULT hr = m_pConnection-> Open (ConnectionString, UserID, Password, NULL );
If (TRUE = FAILED (hr ))
{
Return false;
}
M_pCommand-> ActiveConnection = m_pConnection;
Return true;
}
Catch (_ com_error & e)
{
PrintErrorInfo (e );
Return false;
}
}
_ RecordsetPtr CDBOperation: ExecuteWithResSQL (const char * SQL)
{
Try
{
M_pCommand-> CommandText = _ bstr_t (SQL );
_ RecordsetPtr pRst = m_pCommand-> Execute (NULL, NULL, ad1_text );
Return pRst;
}
Catch (_ com_error & e)
{
PrintErrorInfo (e );
Return NULL;
}
}
Void CDBOperation: PrintErrorInfo (_ com_error & e)
{
Printf ("Error infomation are as follows \ n ");
Printf ("ErrorNo: % d \ nError Message: % s \ nError Source: % s \ nError Description: % s \ n", e. error (), e. errorMessage (), (LPCTSTR) e. source (), (LPCTSTR) e. description ());
}
 
_ ConnectionPtr CDBOperation: CreateConnPtr ()
{
HRESULT hr;
_ ConnectionPtr connPtr;
Hr = connPtr. CreateInstance (_ uuidof (Connection ));
If (FAILED (hr) = TRUE)
{
Return NULL;
}
Return connPtr;
}
 
_ CommandPtr CDBOperation: createcommp tr ()
{
HRESULT hr;
_ CommandPtr commp TR;
Hr = commp tr. CreateInstance (_ uuidof (Command ));
If (FAILED (hr) = TRUE)
{
Return NULL;
}
Return commp TR;
}
 
_ RecordsetPtr CDBOperation: CreateRecsetPtr ()
{
HRESULT hr;
_ RecordsetPtr recsetPtr;
Hr = recsetPtr. CreateInstance (_ uuidof (Command ));
If (FAILED (hr) = TRUE)
{
Return NULL;
}
Return recsetPtr;
}

# Include "stdafx. h"
# Include "DBOperation. h"
CDBOperation: CDBOperation (void)
{
CoInitialize (NULL );
M_pConnection = CreateConnPtr ();
M_pCommand = createcomatrix tr ();
}
CDBOperation ::~ CDBOperation (void)
{
M_pConnection-> Close ();
}
Bool CDBOperation: ConnToDB (char * ConnectionString, char * UserID, char * Password)
{
If (NULL = m_pConnection)
{
Printf ("Failed to create connection \ n ");
Return false;
}
Try
{
HRESULT hr = m_pConnection-> Open (ConnectionString, UserID, Password, NULL );
If (TRUE = FAILED (hr ))
{
Return false;
}
M_pCommand-> ActiveConnection = m_pConnection;
Return true;
}
Catch (_ com_error & e)
{
PrintErrorInfo (e );
Return false;
}
}
_ RecordsetPtr CDBOperation: ExecuteWithResSQL (const char * SQL)
{
Try
{
M_pCommand-> CommandText = _ bstr_t (SQL );
_ RecordsetPtr pRst = m_pCommand-> Execute (NULL, NULL, ad1_text );
Return pRst;
}
Catch (_ com_error & e)
{
PrintErrorInfo (e );
Return NULL;
}
}
Void CDBOperation: PrintErrorInfo (_ com_error & e)
{
Printf ("Error infomation are as follows \ n ");
Printf ("ErrorNo: % d \ nError Message: % s \ nError Source: % s \ nError Description: % s \ n", e. error (), e. errorMessage (), (LPCTSTR) e. source (), (LPCTSTR) e. description ());
}

_ ConnectionPtr CDBOperation: CreateConnPtr ()
{
HRESULT hr;
_ ConnectionPtr connPtr;
Hr = connPtr. CreateInstance (_ uuidof (Connection ));
If (FAILED (hr) = TRUE)
{
Return NULL;
}
Return connPtr;
}

_ CommandPtr CDBOperation: createcommp tr ()
{
HRESULT hr;
_ CommandPtr commp TR;
Hr = commp tr. CreateInstance (_ uuidof (Command ));
If (FAILED (hr) = TRUE)
{
Return NULL;
}
Return commp TR;
}

_ RecordsetPtr CDBOperation: CreateRecsetPtr ()
{
HRESULT hr;
_ RecordsetPtr recsetPtr;
Hr = recsetPtr. CreateInstance (_ uuidof (Command ));
If (FAILED (hr) = TRUE)
{
Return NULL;
}
Return recsetPtr;
} My code is placed in a button Click event of MFC:

Remember to import the header file # include "DBOperation. h" to the cpp file that handles the event"

[Cpp]
CDBOperation dbOper;
Bool bConn = dbOper. ConnToDB ("Provider = OraOLEDB. Oracle.1; Persist Security Info = True; Data Source = boss", "User Name", "password ");
If (false = bConn)
{
MessageBox (LPCTSTR) "An error occurred while connecting to the database \ 0 );
Return;
}
 
// Query
_ RecordsetPtr pRst;
Char SQL [255] = {0 };
Strcpy (SQL, "select * from boss_test_table2 where rownum = 1 ");
PRst = dbOper. ExecuteWithResSQL (SQL );
If (NULL = pRst)
{
MessageBox (_ T ("An error occurred while querying data! \ 0 "), 0, 0 );
Return;
}
If (pRst-> adoEOF)
{
PRst-> Close ();
MessageBox (LPCTSTR) "There is no records in this table \ 0", 0, 0 );
Return;
}
_ Variant_t vSno, vName;
While (! PRst-> adoEOF)
{
// PRst-> MoveFirst (); // the record set pointer moves to the front of the query result set
VSno = pRst-> GetCollect (_ variant_t ("U_NUMBER "));
VName = pRst-> GetCollect (_ variant_t ("USERS_NAME "));
MessageBox (LPCTSTR) (_ bstr_t) vSno, 0, 0 );
PRst-> MoveNext ();
}
 
Strcpy (SQL, "insert into boss_test_table2 (u_number, users_name, users_phone, status, customno_id) values ('123', 'C + TTT + ', '123', 2, 'ppppppppup ')");
PRst = dbOper. ExecuteWithResSQL (SQL );
If (NULL! = PRst)
{
AfxMessageBox (_ T ("data inserted successfully \ n "));
}
// Execute the delete statement
Sprintf (SQL, "delete boss_test_table2 where u_number = '% S'", "009 ");
PRst = dbOper. ExecuteWithResSQL (SQL );
If (NULL! = PRst)
{
MessageBox (_ T ("data deleted successfully \ 0"), 0, 0 );
}
// Execute the update statement
Sprintf (SQL, "update boss_test_table2 set users_name = '% S'", "C ++ anti-human, MFC anti-social ");
PRst = dbOper. ExecuteWithResSQL (SQL );
If (NULL! = PRst)
{
MessageBox (_ T ("data updated successfully \ 0"), 0, 0 );
}

CDBOperation dbOper;
Bool bConn = dbOper. ConnToDB ("Provider = OraOLEDB. Oracle.1; Persist Security Info = True; Data Source = boss", "User Name", "password ");
If (false = bConn)
{
MessageBox (LPCTSTR) "An error occurred while connecting to the database \ 0 );
Return;
}

// Query
_ RecordsetPtr pRst;
Char SQL [255] = {0 };
Strcpy (SQL, "select * from boss_test_table2 where rownum = 1 ");
PRst = dbOper. ExecuteWithResSQL (SQL );
If (NULL = pRst)
{
MessageBox (_ T ("An error occurred while querying data! \ 0 "), 0, 0 );
Return;
}
If (pRst-> adoEOF)
{
PRst-> Close ();
MessageBox (LPCTSTR) "There is no records in this table \ 0", 0, 0 );
Return;
}
_ Variant_t vSno, vName;
While (! PRst-> adoEOF)
{
// PRst-> MoveFirst (); // the record set pointer moves to the front of the query result set
VSno = pRst-> GetCollect (_ variant_t ("U_NUMBER "));
VName = pRst-> GetCollect (_ variant_t ("USERS_NAME "));
MessageBox (LPCTSTR) (_ bstr_t) vSno, 0, 0 );
PRst-> MoveNext ();
}

Strcpy (SQL, "insert into boss_test_table2 (u_number, users_name, users_phone, status, customno_id) values ('123', 'C + TTT + ', '123', 2, 'ppppppppup ')");
PRst = dbOper. ExecuteWithResSQL (SQL );
If (NULL! = PRst)
{
AfxMessageBox (_ T ("data inserted successfully \ n "));
}
// Execute the delete statement
Sprintf (SQL, "delete boss_test_table2 where u_number = '% S'", "009 ");
PRst = dbOper. ExecuteWithResSQL (SQL );
If (NULL! = PRst)
{
MessageBox (_ T ("data deleted successfully \ 0"), 0, 0 );
}
// Execute the update statement
Sprintf (SQL, "update boss_test_table2 set users_name = '% S'", "C ++ anti-human, MFC anti-social ");
PRst = dbOper. ExecuteWithResSQL (SQL );
If (NULL! = PRst)
{
MessageBox (_ T ("data updated successfully \ 0"), 0, 0 );
}