I created this classes�to make it easy to work
with ODBC. For this I created the CODBCDatabase and CODBCRecordset classes
The CODBCDatabase Class
CODBCDatabase::CODBCDatabase
Constructs a CODBCDatabase object.
CODBCDatabase();
See sample
CODBCDatabase::Open
The Open establishes connections to a driver and a data source.
BOOL Open(CHAR* lpstrDSN, CHAR* lpstrUser = NULL, CHAR* lpstrPass = NULL);
Parameters
CHAR* lpstrDSN Pointer to a null-terminated string containing the data source name
CHAR* lpstrUser = NULL Pointer to a null-terminated string containing the user identifier
CHAR* lpstrPass = NULL Pointer to a null-terminated string containing the authentication string (typically the password).
If the function succeeds, this returns TRUE.
See sample
CODBCDatabase::DriverConnect
DriverConnect supports data sources that require more connection information than the three arguments in Open function,
dialog boxes to prompt the user for all connection information, and data sources that are not defined in the system information.
BOOL DriverConnect(CHAR* szConnStr, CHAR* szConnStrOut = NULL, HWND hWnd = NULL, enum drvCompletion drvConn = sqlNoPrompt);
Parameters
CHAR* szConnStrPointer to a null-terminated string containing a full connection string (see the syntax in "Comments"), a partial connection string, or an empty string.
CHAR* szConnStrOut = NULL Pointer to a buffer for the completed connection string.
HWND hWnd = NULL Window handle. The application can pass the handle of the parent window, if applicable, or a null pointer
if either the window handle is not applicable or DriverConnect will not present any dialog boxes.
enum drvCompletion drvConn Flag that indicates whether the Driver Manager or driver must prompt for more connection information:
����CODBCDatabase::sqlNoPrompt
����CODBCDatabase::sqlPrompt
If the function succeeds, this returns TRUE.
See sample
CODBCDatabase::SetReadOnly
The SetReadOnly indicator that the connection is not required to support SQL statements that
cause updates to occur.
void SetReadOnly(BOOL bReadOnly = TRUE);
Parameters
BOOL bReadOnly = TRUE Set read only
If the function succeeds, this returns TRUE.
CODBCDatabase::SetLoginTimeout
The SetLoginTimeout set the number of seconds to wait for a login request to complete before returning to the application.
void SetLoginTimeout(LONG nSeconds);
Parameters
LONG nSeconds The time in seconds. If it is 0, the timeout is disabled and a connection attempt will wait indefinitely.
CODBCDatabase::SetConnectionTimeout
The SetConnectionTimeout set the number of seconds to wait for any request on the connection to complete before returning to the application.
void SetConnectionTimeout(LONG nSeconds);
Parameters
LONG nSeconds The time in seconds
See sample
CODBCDatabase::GetConnectionTimeout
The GetConnectionTimeout returns the time n seconds of connection timeout.
LONG GetConnectionTimeout();
CODBCDatabase::Execute
The Execute function executes a SQL preparable statement.
BOOL Execute(CHAR* szSqlStr);
Parameters
CHAR* szSqlStr
Pointer to a null-terminated
string containing the SQL statement to be executed
If the function succeeds, this returns TRUE.
See sample
CODBCDatabase pdb;
if(!pdb.DriverConnect("DSN=Test;SERVER=ServerSQL;UID=;PWD=;DATABASE=TestDatabase;"))
return FALSE;
pdb.Execute("Delete Test Where Field1 >= 17");
n = pdb.GetRowsAffected();
CODBCDatabase::GetRowsAffected
The GetRowsAffected returns the number of rows affected for the last Execute.
int GetRowsAffected();
See sample
CODBCDatabase::IsConnected
The IsConnected returns true if the connection to database is open.
BOOL IsConnected();
CODBCDatabase::Close
The Close function closes the connection.
void Close();
See sample
The CODBCRecordset Class
CODBCRecordset::CODBCRecordset
Constructs a CODBCRecordset object.
CODBCRecordset(CODBCDatabase* pDb);
Parameters
CODBCDatabase* pDb Pointer to the CODBCDatabase Object.
See sample
CODBCRecordset::Open
The Open executes a preparable SQL statement.
BOOL Open(CHAR* szSqlStr);
Parameters
CHAR* szSqlStr Pointer to a null-terminated string containing a SQL statement.
See sample
CODBCRecordset::GetFieldLength
The GetFieldLength returns the size of the Field on the data source.
LONG GetFieldLength(int nField);
Parameters
int nField Field Index of result data, ordered sequentially in increasing Field order, starting at 0
CODBCRecordset::GetFieldIndex
The GetFieldIndex returns the index of a specific field name. If the field name don't exist GetFieldIndex returns -1.
int GetFieldIndex(CHAR* szFieldName);
Parameters
CHAR* szFieldName Pointer to a null-terminated string containing the Field Name.
CODBCRecordset::GetFieldName
The GetFieldName returns the field name in the result set.
BOOL GetFieldName(int nField, CHAR* szFieldName);
Parameters
int nField
CHAR* szFieldName Pointer to a buffer in which to return the Field Name.
CODBCRecordset::GetFieldAttributes
The GetFieldAttributes returns the result descriptor�field name, type, field size-for one column in the result set.
BOOL GetFieldAttributes(int nField, CHAR* szFieldName, int& nType, int& nLength);
Parameters
int nField Field Index of result data, ordered sequentially in increasing Field order, starting at 0
CHAR* szFieldName Pointer to a buffer in which to return the Field Name.
int& nType Pointer to a buffer in which to return the SQL Data Type of the Field.
int& nLength Pointer to a buffer in which to return the size of the Field on the data source.
See sample
Data Types
����CODBCRecordset::typeChar
����CODBCRecordset::typeVarChar
����CODBCRecordset::typeLongVarChar
����CODBCRecordset::typeWChar
����CODBCRecordset::typeWVarChar
����CODBCRecordset::typeWLongVarChar
����CODBCRecordset::typeDecimal
����CODBCRecordset::typeNumeric
����CODBCRecordset::typeSmallint
����CODBCRecordset::typeInteger
����CODBCRecordset::typeReal
����CODBCRecordset::typeFloat
����CODBCRecordset::typeDouble
����CODBCRecordset::typeBit
����CODBCRecordset::typeTinyint
����CODBCRecordset::typeBigInt
����CODBCRecordset::typeBinary
����CODBCRecordset::typeVarBinary
����CODBCRecordset::typeLongVarBinary
����CODBCRecordset::typeDate
����CODBCRecordset::typeTime
����CODBCRecordset::typeTimeStamp
����CODBCRecordset::typeIntervalMonth
����CODBCRecordset::typeIntervalYear
����CODBCRecordset::typeIntervalYearToMonth
����CODBCRecordset::typeIntervalDay
����CODBCRecordset::typeIntervalHour
����CODBCRecordset::typeIntervalMinute
����CODBCRecordset::typeIntervalSecond
����CODBCRecordset::typeIntervalDayToHour
����CODBCRecordset::typeIntervalDayToMinute
����CODBCRecordset::typeIntervalDayToSecond
����CODBCRecordset::typeIntervalHourToMinute
����CODBCRecordset::typeIntervalHourToSecond
����CODBCRecordset::typeIntervalMinuteToSecond
����CODBCRecordset::typeGUID
CODBCRecordset::GetFieldCount
The GetFieldCount returns the number of fields in the result set.
int GetFieldCount();
CODBCRecordset::GetFieldValue
The GetFieldValue.
BOOL GetFieldValue(int nField, CHAR* szData);
BOOL GetFieldValue(CHAR* szFieldName, CHAR *szData);
BOOL GetFieldValue(int nField, LONG *lData);
BOOL GetFieldValue(CHAR* szFieldName, LONG *lData);
BOOL GetFieldValue(int nField, DOUBLE *dblData);
BOOL GetFieldValue(CHAR* szFieldName, DOUBLE *dblData);
BOOL GetFieldValue(int nField, struct tm* time);
BOOL GetFieldValue(CHAR* szFieldName, struct tm* time);
Parameters
int nField Field Index of result data, ordered sequentially in increasing Field order,
starting at 0
CHAR* szFieldName Pointer to a null-terminated string containing the Field Name
CHAR* szData Pointer to the buffer in which to return the data.
LONG *lData Pointer to a null-terminated string buffer in which to return the data.
DOUBLE *dblData Pointer to a double buffer in which to return the data.
struct tm* time Pointer to a time struct buffer in which to return the data
If the function succeeds, this returns TRUE.
See sample
CODBCRecordset::MoveFirst
The MoveFirst makes the First record of the recordset the current record.
BOOL MoveFirst();
If the function succeeds, this returns TRUE.
CODBCRecordset::MoveNext
The MoveNext makes the Next record of the recordset the current record.
BOOL MoveNext();
If the function succeeds, this returns TRUE.
See sample
CODBCRecordset::MovePrevious
The MovePrevious makes the Previous record of the recordset the current record.
BOOL MovePrevious();
If the function succeeds, this returns TRUE.
CODBCRecordset::MoveLast
The MoveLast makes the Last record of the recordset the current record.
BOOL MoveLast();
If the function succeeds, this returns TRUE.
CODBCRecordset::IsEof
The IsEof returns true if the current position contains no records.
BOOL IsEof();
If the function succeeds, this returns TRUE.
See sample
CODBCRecordset::IsBof
The IsBof returns true if the current position is the bottom of the recordset.
BOOL IsBof();
If the function succeeds, this returns TRUE.
CODBCRecordset::Close
The Close.
void Close();
See sample
Sample:
CODBCDatabase pdb;
pdb.SetConnectionTimeout(15);
if(!pdb.DriverConnect("DSN=Test;SERVER=ServerSQL;UID=;PWD=;DATABASE=TestDatabase;"))
return FALSE;
CODBCRecordset prs = CODBCRecordset(&pdb);
prs.Open("Select * From test");
char szData[256];
while(!prs.IsEof())
{
int nType;
long lData;
double dblData;
int nLen;
struct tm time;
prs.GetFieldAttributes(0, NULL, nType, nLen);
switch(nType)
{
case CODBCRecordset::typeChar:
case CODBCRecordset::typeVarChar:
memset(szData, 0, sizeof(szData));
prs.GetFieldValue(0, szData);
break;
}
prs.GetFieldValue(1, &lData);
memset(szData, 0, sizeof(szData));
prs.GetFieldValue(2, szData);
prs.GetFieldValue(3, &time);
memset(szData, 0, sizeof(szData));
prs.GetFieldValue(4, szData);
dblData = 0;
prs.GetFieldValue(5, &dblData);
dblData = 0;
prs.GetFieldValue(6, &dblData);
prs.MoveNext();
}
prs.Close();
pdb.Close();
Carlos A. Antollini.
Updates
14 August 2001 Version 1.0 Released.
29 August 2001 Updated source files.
Special thanks
The CODBC* class have received many suggestions from the readers.
Thank to All for your colaboration.
