I created these classes to make it easy to work with ADO. For this I created the CADODatabse
class and the CADORecordset
class.
The CADODatabase
class has a set of functions that corresponds to the _ConnectionPtr
.
CADODatabase::CADODatabase
Creates a CADODatabase
object.
CADODatabase();
CADODatabase::Open
The Open
function opens a connection to a database.
BOOL Open(LPCTSTR lpstrConnection = _T(""));
throw(CADOException);
Parameters
LPCTSTR lpstrConnection
- The connection string.
See Sample
Note: the class has the function SetConnectionString
. You can insert the connection string through this function. In this case you can do the following:
CADODatabase* pAdoDb = new CADODatabase();
CString strConnection = _T("");
strConnection = _T("Provider=MSDASQL;PersistSecurityInfo=False;"
"Trusted_Connection=Yes;"
"Data Source=Access Sql Server;catalog=sampledb");
pAdoDb->SetConnectionString(strConnection);
if(pAdoDb->Open())
DoSomething();
.
.
.
CADODatabase* pAdoDb = new CADODatabase();
CString strConnection = _T("");
strConnection = _T("Provider=Microsoft.Jet.OLEDB.4.0;"
"Data Source=C:\\VCProjects\\ADO\\Test\\dbTest.mdb");
pAdoDb->SetConnectionString(strConnection);
if(pAdoDb->Open())
{
DoSomething();
.
.
.
pAdoDb->Close();
}
delete pAdoDb;
CADODatabase::Execute
The Execute
function executes a SQL statement in the open database.
BOOL Execute(LPCTSTR lpstrExec);
throw(CADOException);
Parameters
LPCTSTR lpstrExec
- A string pointer containing the SQL statement to execute.
CADODatabase* pAdoDb = new CADODatabase();
CString strConnection = _T("");
strConnection = _T("Provider=MSDASQL;"
"PersistSecurityInfo=False;"
"Trusted_Connection=Yes"
"Data Source=Access Sql Server;catalog=sampledb");
if(pAdoDb->Open(strConnection))
pAdoDb->Execute("Delete From tblClients Where Cheker = 3");
Return Value
The function returns TRUE
if it was executed successfully.
CADODatabase::GetRecordsAffected
The GetRecordsAffcted
function returns the number of records affected by the last SQL statement executed.
int GetRecordsAffected();
CADODatabase::GetActiveConnection
The GetActiveConnection
returns the active connection.
_ConnectionPtr GetActiveConnection();
CADODatabase::GetRecordCount
GetRecordCount
returns the number of records affected in a query.
DWORD GetRecordCount(_RecordsetPtr m_pRs);
Parameters
_RecorsetPtr m_Prs
- The recordset.
CADODatabase::BeginTransaction
Call this function to initiate a transaction. After you call BeginTransaction
, updates you make to your data take effect when you commit the transaction.
long BeginTransaction();
CADODatabase::CommitTransaction
Call CommitTransaction
function to commit a transaction, for example, save a group of edits and updates to one or more databases.
long CommitTransaction();
CADODatabase::RollbackTransaction
Call RollbackTransaction
function to end the current transaction and restore all databases to their condition before the transaction was begun.
long RollbackTransaction();
CADODatabase::IsOpen
The IsOpen
function returns the status of the connection with the database.
BOOLIsOpen();
Return Value
The function returns TRUE
if the connection to the database is open.
CADODatabase::Close
The Close
function closes the connection to the database.
void Close();
CADODatabase::SetConnectionString
With the SetConnectionString
, you can insert the connection string.
void SetConnectionString(LPCTSTR lpstrConnection);
Parameters
LPCTSTR lpstrConnection
- A connection string used for opening the database.
See CADODatabase::Open();
CADODatabase::GetConnectionString
The GetConnectionString
function returns the connection string used for making a connection with a database.
CString GetConnectionString();
CADODatabase::SetConnectionMode
The SetConnectionMode
function sets the mode of connection.
void SetConnectionMode(cadoConnectModeEnum nMode);
Parameters
cadoConnectModeEnum nMode
- a variable that defines the connection mode to be used. It can be one of the following:
CADODatabase::connectModeUnknown
CADODatabase::connectModeRead
CADODatabase::connectModeWrite
CADODatabase::connectModeReadWrite
CADODatabase::connectModeShareDenyRead
CADODatabase::connectModeShareDenyWrite
CADODatabase::connectModeShareExclusive
CADODatabase::connectModeShareDenyNone
CADODatabase::GetLastError
The GetLastError
function returns the last error code.
DWORD GetLastError();
CADODatabase::GetLastErrorString
The GetLastErrorString
function returns the last error string.
CString GetLastErrorString();
The CADORecordset
class has a set of functions that corresponds to the _RecordsetPtr
.
CADORecordset::CADORecordset
Creates a CADORecordset
object.
CADODatabase();
CADORecordset(CADODatabase* pAdoDatabase);
Parameters
CADODatabase* pAdoDatabase
- A CADODatabase
object pointer.
CADORecordset::Open
The Open
function opens a recordset.
BOOL Open(_ConnectionPtr mpdb, LPCTSTR lpstrExec = _T(""),
int nOption = CADORecordset::openUnknown);
BOOL Open(LPCTSTR lpstrExec = _T(""),
int nOption = CADORecordset::openUnknown);
Parameters
_ConnectionPtr mpdb
- A connection pointer.
LPCTSTR lpstrExec
- A string pointer containing an SQL SELECT
statement.
int nOption
- An integer that defines the access mode. The values are as follows:
CADORecordset::openUnknown
CADORecordset::openQuery
CADORecordset::openTable
CADORecordset::openStoredProc
Return Value
Returns TRUE
if it was executed successfully.
See Sample
CADORecordset::Execute
The Execute
function opens a recordset.
BOOL Execute(CADOCommand* pCommand);
throw(CADOException);
Parameters
CADOCommand* pCommand
- A CADOCommand
pointer.
Return Value
Returns TRUE
if it was executed successfully.
See Sample
CADORecordset::GetQuery;
GetQuery
returns the string containing the SQL SELECT
statement.
CString GetQuery();
CADORecordset::SetQuery
void SetQuery(LPCSTR strQuery);
Parameters
LPCTSTR strQuery
- A string pointer containing an SQL SELECT
statement.
CADORecordset::RecordBinding
BOOL RecordBinding(CADORecordBinding pAdoRecordBinding);
Parameters
CADORecordBinding pAdoRecordBinding
CADORecordset::GetRecordCount
GetRecordCount
returns the number of records accessed in the recordset.
DWORD GetRecordCount();
See Sample
CADORecordset::IsOpen
IsOpen
determines if the recordset is open.
BOOL IsOpen();
Return Value
This member function returns TRUE
if the recordset has not been closed.
CADORecordset::Close
The Close
function closes the recordset.
void Close();
See Sample
CADORecordset::GetFieldCount
The GetFieldCount
function returns the number of fields in the recordset.
long GetFieldCount();
CADORecordset::GetFieldValue
The GetFieldValue
function returns a value that contains the value of a field.
BOOL GetFieldValue(LPCTSTR lpFieldName, int nValue);
BOOL GetFieldValue(int nIndex, int nValue);
BOOL GetFieldValue(LPCTSTR lpFieldName, long lValue);
BOOL GetFieldValue(int nIndex, long lValue);
BOOL GetFieldValue(LPCTSTR lpFieldName, unsigned long ulValue);
BOOL GetFieldValue(int nIndex, unsigned long ulValue);
BOOL GetFieldValue(LPCTSTR lpFieldName, double dbValue);
BOOL GetFieldValue(int nIndex, double dbValue);
BOOL GetFieldValue(LPCTSTR lpFieldName, CString strValue,
CString strDateFormat = _T(""));
BOOL GetFieldValue(int nIndex, CString strValue,
CString strDateFormat = _T(""));
BOOL GetFieldValue(LPCTSTR lpFieldName, COleDateTime time);
BOOL GetFieldValue(int nIndex, COleDateTime time);
BOOL GetFieldValue(LPCTSTR lpFieldName, bool bValue);
BOOL GetFieldValue(int nIndex, bool bValue);
BOOL GetFieldValue(LPCTSTR lpFieldName, COleCurrency cyValue);
BOOL GetFieldValue(int nIndex, COleCurrency cyValue);
throw(CADOException);
Parameters
LPCTSTR lpFieldName
- A pointer to a string that contains the name of a field.
int nIndex
- A zero-based index of the field in the recordset�s Fields
collection, for lookup by index.
double dbValue
- A reference to an object that will store the value of a field.
long lValue
- A reference to an object that will store the value of a field.
unsigned long ulValue
- A reference to an object that will store the value of a field.
int nValue
- A reference to an object that will store the value of a field.
CString strValue
- A reference to an object that will store the value of a field.
CString strDateFormat
- A formatting time string similar to the strftime
formatting string. The more common are:
- %a - Abbreviated weekday name
- %A - Full weekday name
- %b - Abbreviated month name
- %B - Full month name
- %c - Date and time representation appropriate for locale
- %d - Day of month as decimal number (01 - 31)
- %H - Hour in 24-hour format (00 - 23)
- %I - Hour in 12-hour format (01 - 12)
- %j - Day of year as decimal number (001 - 366)
- %m - Month as decimal number (01 - 12)
- %M - Minute as decimal number (00 - 59)
- %p - Current locale�s A.M./P.M. indicator for 12-hour clock
- %S - Second as decimal number (00 - 59)
- %U - Week of year as decimal number, with Sunday as first day of week (00 - 53)
- %w - Weekday as decimal number (0 - 6; Sunday is 0)
- %W - Week of year as decimal number, with Monday as first day of week (00 - 53)
- %x - Date representation for current locale
- %X - Time representation for current locale
- %y - Year without century, as decimal number (00 - 99)
- %Y - Year with century, as decimal number
COleDateTime time
- A reference to an object that will store the value of a field.
bool bValue
- A reference to an object that will store the value of a field.
COleCurrency cyValue
- A reference to an object that will store the value of a field.
See Sample
CADORecordset::IsFieldNull
The IsFieldNull
function determines if the field data is null.
BOOL IsFieldNull(LPCTSTR lpFieldName);
BOOL IsFieldNull(int nIndex);
throw(CADOException);
Parameters
LPCTSTR lpFieldName
- A pointer to a string that contains the name of a field.
int nIndex
- A zero-based index of the field in the recordset�s Fields
collection, for lookup by index.
Return Value
This function returns TRUE
if the field data is null.
CADORecordset::IsFieldEmpty
The IsFieldEmpty
function determines if the field data is empty.
BOOL IsFieldEmpty(LPCTSTR lpFieldName);
BOOL IsFieldEmpty(int nIndex);
throw(CADOException);
Parameters
LPCTSTR lpFieldName
- A pointer to a string that contains the name of a field.
int nIndex
- A zero-based index of the field in the recordset�s Fields
collection, for lookup by index.
Return Value
This function returns TRUE
if the field data is empty.
CADORecordset::IsEof
BOOL IsEof();
Return Value
This function returns TRUE
if the current position contains no records.
See Sample
CADORecordset::IsBof
BOOL IsBof();
Return Value
This function returns TRUE
if the current position is the bottom of the recordset.
CADORecordset::MoveFirst
CADORecordset::MoveNext
CADORecordset::MovePrevious
CADORecordset::MoveLast
These functions make the first/next/previous/or last record of the recordset as the current record.
void MoveFirst();
void MoveNext();
void MovePrevious();
void MoveLast();
See Sample
CADORecordset::GetAbsolutePage
CADORecordset::SetAbsolutePage
Indicates on which page the current record resides.
long GetAbsolutePage();
void SetAbsolutePage(int nPage);
Parameters
int nPage
- The number of the page starting from 1.
See Sample
CADORecordset::GetPageCount
GetPageCount
returns the number of pages in the recordset.
long GetPageCount();
See Sample
CADORecordset::GetPageSize
CADORecordset::SetPageSize
Indicates the number of records per page.
long GetPageSize();
void SetPageSize(int nSize);
Parameters
int nSize
- set the number of records per page.
For example
CADORecordset* pRs = new CADORecordset(pDb);
if(pRs->Open("MyBigTable", CADORecordset::openTable))
{
pRs->SetPageSize(5);
for(register int nPageIndex = 1; nPageIndex <= pRs->GetPageCount();
nPageIndex++)
{
pRs->SetAbsolutePage(nPageIndex);
for(register int nRecNumber = 0; nRecNumber < pRs->GetPageSize();
nRecNumber++)
{
long lVal;
pRs->GetFieldValue("ID", lVal);
pRs->MoveNext();
if(pRs->IsEof())
break;
}
}
pRs->Close();
}
delete pRs;
CADORecordset::GetAbsolutePosition
CADORecordset::SetAbsolutePosition
Indicates the position of the record in the recordset.
long GetAbsolutePosition();
void SetAbsolutePosition(int nPosition);
Parameters
int nPosition
- Move to the position in the recordset.
GetAbsolutePosition()
can return the position of the record or one of the following values:
CADORecordset::positionUnknown
CADORecordset::positionBOF
CADORecordset::positionEOF
CADORecordset::GetFieldInfo
GetFieldInfo
returns the attributes of a field.
BOOL GetFieldInfo(LPCTSTR lpFieldName, CAdoFieldInfo* fldInfo);
BOOL GetFieldInfo(int nIndex, CAdoFieldInfo* fldInfo);
Parameters
LPCTSTR lpFieldName
- A pointer to a string that contains the name of a field.
int nIndex
- A zero-based index of the field in the recordset's Fields
collection, for lookup by index.
CAdoFieldInfo* fldInfo
- A struct that returns the field attributes.
struct CADOFieldInfo
{
char m_strName[30];
short m_nType;
long m_lSize;
long m_lDefinedSize;
long m_lAttributes;
short m_nOrdinalPosition;
BOOL m_bRequired;
BOOL m_bAllowZeroLength;
long m_lCollatingOrder;
};
The element m_nType
of the class CADOFieldInfo
can be one of the following values:
CADORecordset::typeEmpty
CADORecordset::typeTinyInt
CADORecordset::typeSmallInt
CADORecordset::typeInteger
CADORecordset::typeBigInt
CADORecordset::typeUnsignedTinyInt
CADORecordset::typeUnsignedSmallInt
CADORecordset::typeUnsignedInt
CADORecordset::typeUnsignedBigInt
CADORecordset::typeSingle
CADORecordset::typeDouble
CADORecordset::typeCurrency
CADORecordset::typeDecimal
CADORecordset::typeNumeric
CADORecordset::typeBoolean
CADORecordset::typeError
CADORecordset::typeUserDefined
CADORecordset::typeVariant
CADORecordset::typeIDispatch
CADORecordset::typeIUnknown
CADORecordset::typeGUID
CADORecordset::typeDate
CADORecordset::typeDBDate
CADORecordset::typeDBTime
CADORecordset::typeDBTimeStamp
CADORecordset::typeBSTR
CADORecordset::typeChar
CADORecordset::typeVarChar
CADORecordset::typeLongVarChar
CADORecordset::typeWChar
CADORecordset::typeVarWChar
CADORecordset::typeLongVarWChar
CADORecordset::typeBinary
CADORecordset::typeVarBinary
CADORecordset::typeLongVarBinary
CADORecordset::typeChapter
CADORecordset::typeFileTime
CADORecordset::typePropVariant
CADORecordset::typeVarNumeric
CADORecordset::typeArray
For example
if(prs->Open("Clients", CADORecordset::openTable))
{
CADOFieldInfo pInfo;
prs->GetFieldInfo("Description", &pInfo);
if(pInfo.m_nType == CADORecordset::typeVarChar)
AfxMessageBox("The type Description Field Is VarChar");
}
if(prs->Open("TestTable", CADORecordset::openTable))
{
CADOFieldInfo* fInfo = new CADOFieldInfo;
prs.GetFieldInfo(0, fInfo);
CString strFieldName = fInfo->m_strName;
prs->Close();
}
Return Value
Returns TRUE
if it was executed successfully.
CADORecordset::GetChunk
This function returns all, or a portion, of the contents of a large text or binary data Field
object.
BOOL GetChunk(LPCTSTR lpFieldName, CString& strValue);
BOOL GetChunk(int nIndex, CString& strValue);
BOOL GetChunk(LPCTSTR lpFieldName, LPVOID pData);
BOOL GetChunk(int nIndex, LPVOID pData);
Parameters
LPCTSTR lpFieldName
- A pointer to a string that contains the name of a field.
int nIndex
- A zero-based index of the field in the recordset's Fields
collection, for lookup by index.
CString& strValue
- A string pointer that contains the data that returns from the object.
LPVOID pData
- A pointer that contains the data that returns from the object.
Return Value
Returns TRUE
if it was executd successfully.
See Sample
CADORecordset::AppendChunk
This function appends data to a large text or binary data field.
BOOL AppendChunk(LPCTSTR lpFieldName, LPVOID lpData, UINT nBytes);
BOOL AppendChunk(int nIndex, LPVOID lpData, UINT nBytes);
throw(CADOException);
Parameters
LPCTSTR lpFieldName
- A pointer to a string that contains the name of a field.
int nIndex
- A zero-based index of the field in the recordset's Fields
collection, for lookup by index.
LPVOID lpData
- A pointer that contains the data to append to the object.
UINT nBytes
- A UINT
that indicates the size of the data to be inserted.
Return Value
Returns TRUE
if it was executed successfully.
For example
prs.AddNew();
prs.SetFieldValue("ID", 5);
prs.SetFieldValue("Description", "Client 05");
prs.SetFieldValue("Checker", 1);
prs.AppendChunk("Document",
"This Document is the story of Bob and his Friends...", 37);
prs.Update();
char data[1024];
prs.GetChunk("Document", (LPVOID)&data);
CADORecordset::GetString
This function returns a recordset as a string.
CString GetString(LPCTSTR lpCols, LPCTSTR lpRows, LPCTSTR lpNull,
long numRows = 0);
Parameters
LPCTSTR lpCols
- A columns delimiter.
LPCTSTR lpRows
- A rows delimiter.
LPCTSTR lpNull
- An expression that represents a null value.
long numRows
- The number of rows affected.
CADORecordset::GetLastError
The GetLastError
function returns the last error code.
DWORD GetLastError();
CADORecordset::GetLastErrorString
The GetLastErrorString
function returns the last error string.
CString GetLastErrorString();
CADORecordset::AddNew
The AddNew
function adds a record in the open recordset.
BOOL AddNew();
throw(CADOException);
Return Value
Returns TRUE
if it was executed successfully.
See Sample
CADORecordset::Edit
The Edit
function allows changes to the current record in the open recordset.
void Edit();
CADORecordset::Delete
The Delete
function deletes the current record in the open recordset.
BOOL Delete();
Return Value
Returns TRUE
if it was executed successfully.
CADORecordset::Update
The Update
function updates the pending updates in the current record.
BOOL Update();
throw(CADOException);
Return Value
Returns TRUE
if it was executed successfully.
See Sample
CADORecordset::CancelUpdate
The CancelUpdate
function cancels any pending update in the open recordset.
void CancelUpdate();
CADORecordset::SetFieldValue
The SetFieldValue
function sets the value of a field.
BOOL SetFieldValue(int nIndex, int nValue);
BOOL SetFieldValue(LPCTSTR lpFieldName, int nValue);
BOOL SetFieldValue(int nIndex, long lValue);
BOOL SetFieldValue(LPCTSTR lpFieldName, long lValue);
BOOL SetFieldValue(int nIndex, unsigned long ulValue);
BOOL SetFieldValue(LPCTSTR lpFieldName, unsigned long ulValue);
BOOL SetFieldValue(int nIndex, double dblValue);
BOOL SetFieldValue(LPCTSTR lpFieldName, double dblValue);
BOOL SetFieldValue(int nIndex, CString strValue);
BOOL SetFieldValue(LPCTSTR lpFieldName, CString strValue);
BOOL SetFieldValue(int nIndex, COleDateTime time);
BOOL SetFieldValue(LPCTSTR lpFieldName, COleDateTime time);
BOOL SetFieldValue(int nIndex, bool bValue);
BOOL SetFieldValue(LPCTSTR lpFieldName, bool bValue);
BOOL SetFieldValue(int nIndex, COleCurrency cyValue);
BOOL SetFieldValue(LPCTSTR lpFieldName, COleCurrency cyValue);
Parameters
LPCTSTR lpFieldName
- A pointer to a string that contains the name of a field.
int nIndex
- A zero-based index of the field in the recordset�s Fields
collection, for lookup by index.
int nValue
- A pointer to an object containing the value of the field.
long lValue
- A pointer to an object containing the value of the field.
unsigned long lValue
- A pointer to an object containing the value of the field.
double dbValue
- A pointer to an object containing the value of the field.
CString strValue
- A pointer to an object containing the value of the field.
COleDateTime time
- A pointer to an object containing the value of the field.
bool bValue
- A pointer to an object containing the value of the field.
COleCurrency cyValue
- A pointer to an object containing the value of the field.
Return Value
Returns TRUE
if it was executed successfully.
See Sample
For example
CADORecordset* prs = new CADORecordset(m_pAdoDb);
prs->Open("Test", openTable);
prs->AddNew();
prs->SetFieldValue(0, "dataU");
prs->SetFieldValue(1, "data01");
prs->SetFieldValue(2, (long)51000);
COleDateTime time = COleDateTime(2001,6,15, 10, 8, 30);
prs->SetFieldValue(3, time);
prs->Update();
prs->Close();
delete prs;
CADORecordset::Find
The Find
function locates a string from the current position in the open recordset using an operator of comparison.
BOOL Find(LPCTSTR lpFind,
int nSearchDirection = CADORecordset::searchForward);
Parameters
LPCTSTR lpFind
- A string expression used to locate the record.
int nSearchDirection
- A value that indicates the type of operation. The possible values are:
CADORecordset::searchForward
- Find the next location.
CADORecordset::searchBackward
- Find the previous location.
Return Value
Returns TRUE
if it was executed successfully.
For example
if(prs.Find("Field0 LIKE 'dataU%'"))
{
prs.Delete();
while(prs.FindNext())
prs.Delete();
}
CADORecordset::FindFirst
The FindFirst
function locates a string from the beginning in the open recordset using an operator of comparison.
BOOL FindFirst(LPCTSTR lpFind);
Parameters
LPCTSTR lpFind
- A string expression used to locate the record.
Return Value
Returns TRUE
if it was executed successfully.
CADORecordset::FindNext
The FindNext
function locates a string from the last position in the open recordset using the operator of comparison used in FindFirst
or Find
functions.
BOOL FindNext();
Return Value
Returns TRUE
if it was executed successfully.
See Sample
CADORecordset::GetBookmark
The GetBookmark
function saves the position of the current record.
BOOL GetBookmark();
Return Value
Returns TRUE
if it was executed successfully.
CADORecordset::SetBookmark
The SetBookmark
function returns to the position saved at any time.
void SetBookmark();
Return Value
Returns TRUE
if it was executed successfully.
CADORecordset::SetFilter
The SetFilter
indicates a filter for data in an open Recordset
.
BOOL SetFilter(LPCTSTR strFilter);
throw(CADOException);
Parameters
LPCTSTR strFilter
- a string composed by one or more individual clauses concatenated with AND or OR operators.
Return Value
Returns TRUE
if it was executed successfully.
For example
CADORecordset* pRs = new CADORecordset(pDb);
if(pRs->Open("tblTest", CADORecordset::openTable))
{
CString strFilter = _T("LastName = 'Smith' And Age > 30");
pRs->SetFilter(strFilter);
.
.
pRs->Close();
}
delete pRs
CADORecordset::SetSort
The SetSort
function sets the sort order for records in a CADORecordset
object.
BOOL SetSort(LPCTSTR lpstrCriteria);
throw(CADOException);
Parameters
LPCTSTR lpstrCriteria
- A string that contains the ORDER BY
clause of an SQL statement.
Return Value
Returns TRUE
if it was executed successfully.
CADORecordset::GetRecordset
The GetRecordset
function returns a pointer to an open recordset.
_RecordsetPtr GetRecordset();
CADORecordset::GetActiveConnection
The GetActiveConnection
returns the active connection.
_ConnectionPtr GetActiveConnection();
CADORecordset::Clone
The Clone
function creates a duplicate CADORecordset
object from an existing CADORecordset
object.
BOOL Clone(CADORecordset pAdoRecordset);
throw(CADOException);
Parameters
CADORecordset pAdoRecordset
is an existing CADORecordset
object.
Return Value
Returns TRUE
if it was executed successfully.
For example
CADORecordset m_pRs;
CADORecordset RS;
CADORecordset* pRs = CADORecordset(m_pDb);
if(pRs->Open("tblTest", CADORecordset::openTable))
Recordset
{
pRs->Clone(RS);
long lClonRecs = RS.GetRecordCount();
long lOrigRecs = m_pRs->GetRecordCount();
.
.
RS.Close();
pRs->Close();
}
delete pRs;
CADORecordset::SaveAsXML
The SaveAsXML
function saves the open recordset in a file with XML format.
BOOL SaveAsXML(LPCTSTR lpstrXMLFile);
Parameters
LPCTSTR strXMLFile
- a string that indicates the complete path name of the file where the recordset is to be saved.
Return Value
Returns TRUE
if it was executed successfully.
CADORecordset::OpenXML
The OpenXML
function opens a XML file format in a recordset.
BOOL OpenXML(LPCTSTR lpstrXMLFile);
Parameters
LPCTSTR strXMLFile
- a string that indicates the complete path name of the XML file to be opened.
Return Value
Returns TRUE
if it was executed successfully.
For example
CADORecordset* pRs = CADORecordset(pDB);
if(prs->OpenXML("C:\\My.XML"))
{
CString strClient = _T("");
double dblVal = 0;
long lrecs = prs->GetRecordCount();
if(!prs->IsEof())
prs->MoveFirst();
prs->GetFieldValue("Budget", dblVal);
prs->GetFieldValue("ClientName", strClient);
prs->Close();
}
CADORecordset::OpenSchema
The OpenSchema
function obtains database schema information from the provider.
BOOL OpenSchema(int nSchema, LPCTSTR SchemaID = _T(""));
throw(CADOException);
Parameters
int nSchema
- A value that represents the type of schema query.
LPCTSTR SchemaID = _T("")
- The GUID for a provider-schema query not defined by the OLE DB specification.
Constant |
Value |
Description |
Constraint Columns |
schemaAsserts |
0 |
Returns the assertions defined in the catalog that are owned by a given user.
(ASSERTIONS Rowset) |
CONSTRAINT_ CATALOG *
CONSTRAINT_ SCHEMA *
CONSTRAINT_NAME |
schemaCatalogs |
1 |
Returns the physical attributes associated with catalogs accessible from the DBMS.
(CATALOGS Rowset) |
CATALOG_NAME |
schemaCharacterSets |
2 |
Returns the character sets defined in the catalog that are accessible to a given user.
(CHARACTER_SETS Rowset) |
CHARACTER_ SET_CATALOG *
CHARACTER_ SET_SCHEMA *
CHARACTER_SET _NAME * |
schemaCheckConstraints |
5 |
Returns the check constraints defined in the catalog that are owned by a given user.
(CHECK_CONSTRAINTS Rowset) |
CONSTRAINT_ CATALOG *
CONSTRAINT_ SCHEMA *
CONSTRAINT_NAME |
schemaCollations |
3 |
Returns the character collations defined in the catalog that are accessible to a given user.
(COLLATIONS Rowset) |
COLLATION_ CATALOG *
COLLATION_SCHEMA
COLLATION_NAME |
schemaColumnPrivileges |
13 |
Returns the privileges on columns of tables defined in the catalog that are available to, or granted by, a given user.
(COLUMN_PRIVILEGES Rowset) |
TABLE_CATALOG
TABLE_SCHEMA
TABLE_NAME
COLUMN_NAME
GRANTOR
GRANTEE |
schemaColumns |
4 |
Returns the columns of tables (including views) defined in the catalog that are accessible to a given user.
(COLUMNS Rowset) |
TABLE_CATALOG
TABLE_SCHEMA
TABLE_NAME
COLUMN_NAME |
schemaColumnsDomainUsage |
11 |
Returns the columns defined in the catalog that are dependent on a domain defined in the catalog and owned by a given user.
(COLUMN_DOMAIN_USAGE Rowset) |
DOMAIN_CATALOG
DOMAIN_SCHEMA
DOMAIN_NAME
COLUMN_NAME |
schemaConstraintColumnUsage |
6 |
Returns the columns used by referential constraints, unique constraints, check constraints, and assertions, defined in the catalog and owned by a given user.
(CONSTRAINT_COLUMN_USAGE Rowset) |
TABLE_CATALOG
TABLE_SCHEMA
TABLE_NAME
COLUMN_NAME |
schemaConstraintTableUsage |
7 |
Returns the tables that are used by referential constraints, unique constraints, check constraints, and assertions defined in the catalog and owned by a given user.
(CONSTRAINT_TABLE_USAGE Rowset) |
TABLE_CATALOG
TABLE_SCHEMA
TABLE_NAME |
schemaCubes |
32 |
Returns information about the available cubes in a schema (or the catalog, if the provider does not support schemas).
(CUBES Rowset*) |
CATALOG_NAME
SCHEMA_NAME
CUBE_NAME |
schemaDBInfoKeywords |
30 |
Returns a list of provider-specific keywords.
(IDBInfo::GetKeywords*) |
<None> |
schemaDBInfoLiterals |
31 |
Returns a list of provider-specific literals used in text commands.
(IDBInfo::GetLiteralInfo*) |
<None> |
schemaDimensions |
33 |
Returns information about the dimensions in a given cube. It has one row for each dimension.
(DIMENSIONS Rowset*) |
CATALOG_NAME
SCHEMA_NAME
CUBE_NAME
DIMENSION_NAME
DIMENSION_ UNIQUE_NAME * |
schemaForeignKeys |
27 |
Returns the foreign key columns defined in the catalog by a given user.
(FOREIGN_KEYS Rowset) |
PK_TABLE_CATALOG
PK_TABLE_SCHEMA
PK_TABLE_NAME
FK_TABLE_CATALOG
FK_TABLE_SCHEMA
FK_TABLE_NAME |
schemaHierarchies |
34 |
Returns information about the hierarchies available in a dimension.
(HIERARCHIES Rowset*) |
CATALOG_NAME
SCHEMA_NAME
CUBE_NAME
DIMENSION_ UNIQUE_NAME *
HIERARCHY_NAME
HIERARCHY_ UNIQUE_NAME * |
schemaIndexes |
12 |
Returns the indexes defined in the catalog that are owned by a given user.
(INDEXES Rowset) |
TABLE_CATALOG
TABLE_SCHEMA
INDEX_NAME
TYPE
TABLE_NAME |
schemaKeyColumnUsage |
8 |
Returns the columns defined in the catalog that are constrained as keys by a given user.
(KEY_COLUMN_USAGE Rowset) |
CONSTRAINT_ CATALOG *
CONSTRAINT_ SCHEMA *
CONSTRAINT_NAME
TABLE_CATALOG
TABLE_SCHEMA
TABLE_NAME
COLUMN_NAME |
schemaLevels |
35 |
Returns information about the levels available in a dimension.
(LEVELS Rowset*) |
CATALOG_NAME
SCHEMA_NAME
CUBE_NAME
DIMENSION_ UNIQUE_NAME *
HIERARCHY_ UNIQUE_NAME *
LEVEL_NAME
LEVEL_ UNIQUE_NAME * |
schemaMeasures |
36 |
Returns information about the available measures.
(MEASURES Rowset*) |
CATALOG_NAME
SCHEMA_NAME
CUBE_NAME
MEASURE_NAME
MEASURE_ UNIQUE_NAME * |
schemaMembers |
38 |
Returns information about the available members.
(MEMBERS Rowset*) |
CATALOG_NAME
SCHEMA_NAME
CUBE_NAME
DIMENSION_ UNIQUE_NAME *
HIERARCHY_ UNIQUE_NAME *
LEVEL_ UNIQUE_NAME *
LEVEL_NUMBER
MEMBER_NAME
MEMBER_UNIQUE _NAME *
MEMBER_CAPTION
MEMBER_TYPE Tree operator (For more information, see the OLE DB for OLAP documentation.) |
schemaPrimaryKeys |
28 |
Returns the primary key columns defined in the catalog by a given user.
(PRIMARY_KEYS Rowset) |
PK_TABLE_CATALOG
PK_TABLE_SCHEMA
PK_TABLE_NAME |
schemaProcedureColumns |
29 |
Returns information about the columns of rowsets returned by procedures.
(PROCEDURE_COLUMNS Rowset) |
PROCEDURE_ CATALOG *
PROCEDURE_SCHEMA
PROCEDURE_NAME
COLUMN_NAME |
schemaProcedureParameters |
26 |
Returns information about the parameters and return codes of procedures.
(PROCEDURE_PARAMETERS Rowset) |
PROCEDURE_ CATALOG *
PROCEDURE_SCHEMA
PROCEDURE_NAME
PARAMETER_NAME |
schemaProcedures |
16 |
Returns the procedures defined in the catalog that are owned by a given user.
(PROCEDURES Rowset) |
PROCEDURE_ CATALOG *
PROCEDURE_SCHEMA
PROCEDURE_NAME
PROCEDURE_TYPE |
schemaProperties |
37 |
Returns information about the available properties for each level of the dimension.
(PROPERTIES Rowset*) |
CATALOG_NAME
SCHEMA_NAME
CUBE_NAME
DIMENSION_ UNIQUE_NAME *
HIERARCHY_ UNIQUE_NAME *
LEVEL_ UNIQUE_NAME *
MEMBER_ UNIQUE_NAME *
PROPERTY_TYPE
PROPERTY_NAME |
schemaProviderSpecific |
-1 |
Used if the provider defines its own nonstandard schema queries. |
<Provider specific> |
schemaProviderTypes |
22 |
Returns the (base) data types supported by the data provider.
(PROVIDER_TYPES Rowset) |
DATA_TYPE
BEST_MATCH |
schemaReferentialConstraints |
9 |
Returns the referential constraints defined in the catalog that are owned by a given user.
(REFERENTIAL_CONSTRAINTS Rowset) |
CONSTRAINT_ CATALOG *
CONSTRAINT_ SCHEMA *
CONSTRAINT_NAME |
schemaSchemata |
17 |
Returns the schemas (database objects) that are owned by a given user.
(SCHEMATA Rowset) |
CATALOG_NAME
SCHEMA_NAME
SCHEMA_OWNER |
schemaSQLLanguages |
18 |
Returns the conformance levels, options, and dialects supported by the SQL-implementation processing data defined in the catalog.
(SQL_LANGUAGES Rowset) |
<None> |
schemaStatistics |
19 |
Returns the statistics defined in the catalog that are owned by a given user.
(STATISTICS Rowset) |
TABLE_CATALOG
TABLE_SCHEMA
TABLE_NAME |
schemaTableConstraints |
10 |
Returns the table constraints defined in the catalog that are owned by a given user.
(TABLE_CONSTRAINTS Rowset) |
CONSTRAINT_ CATALOG *
CONSTRAINT_ SCHEMA *
CONSTRAINT_NAME
TABLE_CATALOG
TABLE_SCHEMA
TABLE_NAME
CONSTRAINT_TYPE |
schemaTablePrivileges |
14 |
Returns the privileges on tables defined in the catalog that are available to, or granted by, a given user.
(TABLE_PRIVILEGES Rowset) |
TABLE_CATALOG
TABLE_SCHEMA
TABLE_NAME
GRANTOR
GRANTEE |
schemaTables |
20 |
Returns the tables (including views) defined in the catalog that are accessible to a given user.
(TABLES Rowset) |
TABLE_CATALOG
TABLE_SCHEMA
TABLE_NAME
TABLE_TYPE |
schemaTranslations |
21 |
Returns the character translations defined in the catalog that are accessible to a given user.
(TRANSLATIONS Rowset) |
TRANSLATION_ CATALOG *
TRANSLATION_ SCHEMA *
TRANSLATION _NAME * |
schemaTrustees |
39 |
Reserved for future use. |
|
schemaUsagePrivileges |
15 |
Returns the USAGE privileges on objects defined in the catalog that are available to, or granted by, a given user.
(USAGE_PRIVILEGES Rowset) |
OBJECT_CATALOG
OBJECT_SCHEMA
OBJECT_NAME
OBJECT_TYPE
GRANTOR
GRANTEE |
schemaViewColumnUsage |
24 |
Returns the columns on which viewed tables, defined in the catalog and owned by a given user, are dependent.
(VIEW_COLUMN_USAGE Rowset) |
VIEW_CATALOG
VIEW_SCHEMA
VIEW_NAME |
schemaViews |
23 |
Returns the views defined in the catalog that are accessible to a given user.
(VIEWS Rowset) |
TABLE_CATALOG
TABLE_SCHEMA
TABLE_NAME |
schemaViewTableUsage |
25 |
Returns the tables on which viewed tables, defined in the catalog and owned by a given user, are dependent.
(VIEW_TABLE_USAGE Rowset) |
VIEW_CATALOG
VIEW_SCHEMA
VIEW_NAME |
* Ignore the spaces in these values, as they have been added to avoid page scrolling.
Return Value
Returns TRUE
if it was executed successfully.
For Example
try
{
CAD if(pdb.Open("Data Source=sysdevpdc;Provider="
"MSOLAP;Initial Catalog=Foodmart 2000"))
{
CADORecordset prs(&pdb);
if(prs.OpenSchema(CADORecordset::schemaMeasures))
{
while(!prs.IsEof())
{dset::schemaMeasures))
{
while(!prs.IsEof())
{
CString strValue;
CString strUniqueName;
CString strSqlColumnName;
int nDataType = 0;
int nValue = 0;
prs.GetFieldValue("CUBE_NAME", strValue);
prs.GetFieldValue("MEASURE_NAME", strValue);
prs.GetFieldValue("MEASURE_AGGREGATOR", nValue);
prs.GetFieldValue("MEASURE_UNIQUE_NAME",
strUniqueName);
prs.GetFieldValue("MEASURE_NAME_SQL_COLUMN_NAME",
strSqlColumnName);
prs.GetFieldValue("DATA_TYPE", nDataType);
prs.MoveNext();
}
}
prs.Close();
}
}
catch(CADOException &e)
{
...
}
CADORecordset::Requery
The Requery
function refreshes an open recordset.
BOOL Requery();
throw(CADOException);
Return Value
Returns TRUE
if it was executed successfully.
Sample 01:
CADODatabase* pAdoDb = new CADODatabase();
CString strConnection = "";
strConnection = _T("Provider=MSDASQL;"
"PersistSecurityInfo=False;Trusted_Connection=Yes
Data Source=Access Sql Server;catalog=sampledb");
if(pAdoDb->Open((LPCTSTR)strConnection))
{
CString strQry = _T("");
int numRecords;
strQry.Format(_T("sp_StoreClientFields_ps '%s', %d"),
(LPCTSTR)strParam1, nParam2);
CADORecordset* pRs = new CADORecordset(pAdoDb);
if(!pRs->Open((LPCTSTR)strQry))
{
delete pRs;
delete pAdoDb;
return FALSE
}
numRecords = pRs->GetRecordCount();
while(!pRs->IsEof())
{
CString strVal = _T("");
int nVal = 0;
pRs->GetFieldValue("NumField1", nVal)
pRs->GetFieldValue("StrField..", strVal)
DoSomething(nVal, strVal);
pRs->MoveNext();
}
pRs->Close();
}
else
return FALSE;
The CADOParameter
class has a set of functions that corresponds to the _ParameterPtr
.
CADOParameter::CADOParameter
Creates a CADOParameter
object.
CADOParameter(int nType, long lSize = 0, int nDirection = paramInput,
CString strName = _T(""));
Parameters
int nType
- An int
value that specifies the data type of the CADOParameter
object. Can be one of the values specified in CADORecordset::GetFieldInfo. If you are using CADORecordset::typeNumeric
or CADORecordset::typeDecimal
, you must define the precision and scale values.
long lSize = 0
- An optional long
value that specifies the maximum length for the parameter value in bytes or characters.
int nDirection = paramInput
- An optional int
value that specifies the direction of the CADOParameter
object. Can be one of the following values:
CADOParameter::paramUnknown
- Indicates that the parameter direction is unknown.
CADOParameter::paramInput
- Default. Indicates that the parameter represents an input parameter.
CADOParameter::paramOutput
- Indicates that the parameter represents an output parameter.
CADOParameter::paramInputOutput
- Indicates that the parameter represents both an input and output parameter.
CADOParameter::paramReturnValue
- Indicates that the parameter represents a return value.
CString strName = _T("")
- An optional string that specifies the name of the CADOParameter
object.
See Sample
CADOParameter::SetValue
The SetValue
function sets the value for the CADOParameter
object.
BOOL SetValue(int nValue);
BOOL SetValue(long lValue);
BOOL SetValue(double dbValue);
BOOL SetValue(CString strValue);
BOOL SetValue(COleDateTime time);
BOOL SetValue(_variant_t vtValue);
Parameters
int nValue
- An int
value containing the parameter value.
long lValue
- A long
value containing the parameter value.
double dbValue
- A double
value containing the parameter value.
CString strValue
- A string value containing the parameter value.
COleDateTime time
- A time value containing the parameter value.
_variant_t vtValue
- A variant value containing the parameter value.
Return Value
Returns TRUE
if it was executed successfully.
See Sample
CADOParameter::SetPrecision
The SetPrecison
function sets the precision for the CADOParameter
object.
void SetPrecision(int nPrecision);
CADOParameter::SetScale
The SetScale
function sets the scale for the CADOParameter
object.
void SetScale(int nScale);
CADOParameter::GetValue
The GetValue
function returns the value of the CADOParameter
object.
BOOL GetValue(int& nValue);
BOOL GetValue(long& lValue);
BOOL GetValue(double& dbValue);
BOOL GetValue(CString& strValue, CString strDateFormat = _T(""));
BOOL GetValue(COleDateTime& time);
BOOL GetValue(_variant_t& vtValue);
Parameters
int& nValue
- A reference to an int
that will store the value of the parameter.
long& lValue
- A reference to a long
that will store the value of the parameter.
double& dbValue
- A reference to a double
that will store the value of the parameter.
CString& strValue
- A reference to a string that will store the value of the parameter.
CString strDateFormat = _T("")
- A formatting time string similar to the strftime
formatting string.
COleDateTime& time
- A reference to a time object that will store the value of the parameter.
_variant_t& vtValue
- A reference to a variant object that will store the value of the parameter.
Return Value
Returns TRUE
if it was executed successfully.
See Sample
CADOParameter::SetName
The SetName
function sets the name of the CADOParameter
object.
CString SetName(CString strName);
Parameters
CString strName
- A string specifying the parameter name.
CADOParameter::GetName
The GetName
function returns the CADOParameter
object.
CString GetName();
CADOParameter::GetType
The GetType
function returns the type of the CADOParameter
object.
int GetType();
CADOParameter::GetParameter
The GetParameter
function returns a pointer to a _Parameter
object.
_ParameterPtr GetParameter();
The CADOCommand
class has a set of functions that corresponds to the _CommandPtr
.
CADOCommand::CADOCommand
Creates a CADOCommand
object.
CADOCommand(CADODatabase* pAdoDatabase, CString strCommandText = _T(""),
int nCommandType = typeCmdStoredProc);
Parameters
CADODatabase* pAdoDatabase
- A CADODatabase
object pointer.
CString strCommandText = _T("")
- An optional string that indicates the text of the CADOCcommand
object.
int nCommandType = typeCmdStoredProc
- An optional int
value that indicates the type of the CADOCommand
object. Can be one of the following values:
CADOCommand::typeCmdText
- Evaluates CommandText
as a textual definition of a command or stored procedure call.
CADOCommand::typeCmdTable
- Evaluates CommandText
as a table name whose columns are all returned by an internally generated SQL query.
CADOCommand::typeCmdTableDirect
- Evaluates CommandText
as a table name whose columns are all returned.
CADOCommand::typeCmdStoredProc
- Default. Evaluates CommandText
as a stored procedure name.
CADOCommand::typeCmdUnknown
- Indicates that the type of the command in the CommandText
property is not known.
CADOCommand::typeCmdFile
- Evaluates CommandText
as the file name of a persistently stored recordset. Used with Recordset.Open
or Requery
only.
See Sample
CADOCommand::AddParameter
The AddParameter
function.
BOOL AddParameter(CADOParameter* pAdoParameter);
BOOL AddParameter(CString strName, int nType, int nDirection,
long lSize, int nValue);
BOOL AddParameter(CString strName, int nType, int nDirection,
long lSize, long lValue);
BOOL AddParameter(CString strName, int nType, int nDirection,
long lSize, double dblValue, int nPrecision = 0,
int nScale = 0);
BOOL AddParameter(CString strName, int nType, int nDirection,
long lSize, CString strValue);
BOOL AddParameter(CString strName, int nType, int nDirection,
long lSize, COleDateTime time);
BOOL AddParameter(CString strName, int nType, int nDirection,
long lSize, _variant_t vtValue, int nPrecision = 0,
int nScale = 0);
Parameters
CADOParameter* pAdoParameter
- A pointer to a CADOParameter
object.
CString strName
- A string that specifies the name of the parameter.
int nType
- An int
value that specifies the data type of the CADOParameter
object. Can be one of the values specified in CADORecordset::GetFieldInfo
. If you are using CADORecordset::typeNumeric
or CADORecordset::typeDecimal
, you must define the precision and scale values.
int nDirection
- An int
value that specifies the direction of the CADOParameter
object. Can be one of the values specified in CADOParameter::CADOParameter
.
long lSize
- A long
value that specifies the maximum length for the parameter value in bytes or characters.
int nValue
- An int
value containing the parameter value.
long lValue
- A long
value containing the parameter value.
double dblValue
- A double
value containing the parameter value.
int nPrecision
- An int
value containing the precision of the parameter value.
int nScale
- An int
value containing the scale of the parameter value.
CString strValue
- A string value containing the parameter value.
COleDateTime time
- A time value containing the parameter value.
_variant_t vtValue
- A variant value containing the parameter value.
Return Value
Returns TRUE
if it was executed successfully.
See Sample
CADOCommand::SetText
The SetText
function sets the command text of the CADOCommand
object.
void SetText(CString strCommandText);
Parameters
CString strCommandText
- A string that indicates the command text.
CADOCommand::GetText
The GetText
function returns the command text of the CADOCommand
object.
CString GetText();
CADOCommand::SetType
The SetType
function sets the type of the CADOCommand
object.
void SetType(int nCommandType);
Parameters
int nCommandType
- A int
value that indicates the type of the command.
CADOCommand::GetType
The GetType
function returns the type of the CADOCommand
object.
int GetType();
CADOCommand::GetCommand
The GetCommand
function returns a Command
pointer.
_CommandPtr GetCommand();
CADOCommand::Execute
The Execute
function executes a command text.
BOOLExecute();
Return Value
Returns TRUE
if it was executed successfully.
CADOCommand::GetRecordsAffected
The GetRecordsAffected
function returns the number of records affected by the last command executed.
int GetRecordsAffected();
Sample 02:
//SQL SCRIPT...
Create Procedure sp_OutputTest
@IN1 int,
@OutInt int Output,
@OutChar varchar(20) Output
As
SELECT
@OutChar = 'Hello World'
SELECT
@OutInt = 10 * @IN1
return (90)
GO
//Visual C++ Code...
CADOParameter pParamRetVal(CADORecordset::typeInteger, sizeof(int),
CADOParameter::paramReturnValue);
CADOParameter pParamIn(CADORecordset::typeInteger, sizeof(int));
CADOParameter pParamOutInt(CADORecordset::typeInteger, sizeof(int),
CADOParameter::paramOutput);
CADOParameter pParamOutChar(CADORecordset::typeChar, sizeof(char) * 20,
CADOParameter::paramOutput);
pParamIn.SetValue(2);
CADOCommand pCmd(&pDb, "sp_OutputTest");
pCmd.AddParameter(&pParamRetVal);
pCmd.AddParameter(&pParamIn);
pCmd.AddParameter(&pParamOutInt);
pCmd.AddParameter(&pParamOutChar);
CADORecordset* prs = new CADORecordset(pDb);
if(pRs->Execute(&pCmd))
{
int nVal = 0;
int nRetVal = 0;
CString str = _T("");
pParamRetVal.GetValue(nRetVal);
pParamOutInt.GetValue(nVal);
pParamOutChar.GetValue(str);
}
delete pRS;
The CJetEngine
class has a set of functions that corresponds to the _RecordsetPtr
.
CJetEngine::CompactDatabase
Compacts an Access database.
BOOLCompactDatabase(CString strDatabaseSource, CString strDatabaseDestination)
Parameters
CString strDatabaseSource
- A connection string to the source database.
CString strDatabaseDestination
- A connection string to the destination database.
Remarks:
The connection strings must be like this: "Provider=Microsoft.Jet.OLEDB.4.0;Data Source=C:\the Database Path"
.
Return Value
Returns TRUE
if it was executed successfully.
For example
CString strCompactedDBConnection;
CString strConnection;
CString strCompactedDBPath = _T("C:\\My Projects\\Database\\SampleDB.tmp");
CString strDatabasePath = _T("C:\\My Projects\\Database\\SampleDB.mdb");
strCompactedDBConnection.Format("Provider=Microsoft.Jet.OLEDB."
"4.0;Data Source=%s", strCompactedDBPath.GetBuffer(0));
strConnection.Format("Provider=Microsoft.Jet.OLEDB.4.0;Data Source=%s",
strDatabasePath.GetBuffer(0));
if(CJetEngine::CCompactDatabase(strConnection, strCompactedDBConnection))
{
::CopyFile(strCompactedDBPath.GetBuffer(0),
strDatabasePath.GetBuffer(0), FALSE);
}
The CADOException
class represents an exception condition. The class includes public data members you can use to determine the cause of the exception.
CADOException::CADOException
Creates a CADOException
object.
CADOExcpetion();
To retrieve the ADO error information:
- Construct a
CADOException
object.
- Call any exception object�s
GetErrorMesaage
or GetError
member function, to retrieve information about the error, via the exception object.
For Example
try
{
if(pDb.Open(_T("Provider=Microsoft.JET.OLEDB.4.0;")
_T("Data source = c:\\vc projects\\ado\\dbTest.mdb;")))
{
CADORecordset pRS(&pDb);
if(pRS.Open("tbltest", CADORecordset::openTable))
{
pRS.SetSort("Descriptions");
.
.
.
}
pRS.Close();
}
}
catch(CADOException &e)
{
AfxMessageBox(e.GetErrorMessage());
}
CADOException::GetErrorMessage
CString GetErrorMessage() const;
Return Value
Returns error description.
See Sample
CADOException::GetError
long GetError();
Return Value
Returns the error code.
CADOException::SetError
void SetError(long lErrorCode = 0);
void SetErrorMessage(LPCSTR lpstrError = _T(""));
Parameters
long lErrorCode = 0
- A long
value containing the error code.
LPCSTR lpstrError = _T("")
- A string value containing the error description.
The COLEDBDataLink
class is an utility class to create and edit datalinks.
COLEDBDataLink::COLEDBDataLink
Creates a COLEDBDataLink
object.
COLEDBDataLink();
COLEDBDataLink::New
CString New(HWND hWnd = NULL);
throw(COLEDBException);
Parameters
HWND hWnd = NULL
- The parent window handle.
Return Value
Returns a string informing the connection string corresponding to the created connection.
See Sample
COLEDBDataLink::Edit
void Edit(LPCSTR lpstrConnectionString, HWND hWnd);
throw(COLEDBException);
Parameters
LPCSTR lpstrConnectionString
HWND hWnd
- The parent window handle.
For Example
COLEDBDataLink dtlnk;
try
{
dtlnk.Edit("Provider=Microsoft.JET.OLEDB.4.0;Data source"
" = c:\\vc projects\\ado\\dbTest.mdb;", this->m_hWnd);
}
catch(COLEDBException &e)
{
AfxMessageBox(e.GetErrorMessage());
}
The COLEDBException
class represents an exception condition. The class includes public data members you can use to determine the cause of the exception.
COLEDBException::COLEDBException
Creates a COLEDBException
object.
COLEDBException();
To retrieve the OLEDB error information:
- Construct a
COLEDBException
object.
- Call any exception object�s
GetErrorMessage
or GetError
member function to retrieve information about the error, via the exception object.
For Example
CADODatabase pDb;
COLEDBDataLink dtlnk;
try
{
pDb.Open(dtlnk.New(this->m_hWnd));
}
catch(COLEDBException &e)
{
AfxMessageBox(e.GetErrorMessage());
}
COLEDBException::GetErrorMessage
CString GetErrorMessage() const;
Return Value
Returns error description.
See Sample
COLEDBException::GetError
long GetError();
Return Value
Returns the error code.
COLEDBException::SetError
void SetError(long lErrorCode = 0);
void SetErrorMessage(LPCSTR lpstrError = _T(""));
Parameters
long lErrorCode = 0
- A long
value containing the error code.
LPCSTR lpstrError = _T("")
- A string value containing the error description.
How Bind the MS DataGrid Control to CADORecordset:
- First: You need to add the MS DataGrid Control to your application.
- Second: Apply the
CADORecordset::GetRecordset
function to the SetRefDataSource
function of the data control class.
if(m_pRs.Open("tblTest", CADORecordset::openTable))
{
m_datagridctrl.SetCaption("Clients");
m_datagridctrl.SetRefDataSource(NULL);
m_datagridctrl.SetRefDataSource((LPUNKNOWN)m_pRs.GetRecordset());
m_datagridctrl.Refresh();
}
For reference on how to add a data control to your project, please see this article by Rashid Thadha.
How do I re-sort a Recordset?
The answer is easy. You have several functions and properties that are part of _RecordsetPtr
. Using CADORecordset::GetRecordset()
, you get a pointer to _RecordsetPtr
. You can use it for setting the Sort
property.
Note: You don't need to use _RecordsetPtr::Refresh()
.
if(m_pRs.Open("tblTest", CADORecordset::openTable))
{
m_pRs.GetRecordset()->PutSort("Field01 DESC");
}
Now: you have the function CADORecordset::SetSort();
fatal error C1010: unexpected end of file while looking for precompiled header directive
For solving this common problem, you need to use automatic use of precompiled headers. Select Project/Settings (or ALT+F7) then, in the Project Settings dialog, select the C/C++ tab, then select the Precompiled Headers item in the combo box, and select the Automatic use of precompiled headers option.
How do you get the return codes from your stored procedures in SQL Server?
You must use the CADOParameter
class. CADOParameter::paramReturnValue
gets the value that is returned by the stored procedure. It always must be an integer and must be in the first place in the list of parameters. If you are not using parameters for input or output, you only need to use this parameter....
See Sample
I've been trying to work with the CADOCommand class and be able to pass in a UUID field. I've not been very successful so far. Do you by chance have an example that shows this?
You are talking about uniqueidentifier
type field? Okay, the problem is the following:
First you can update the table using the SQL syntax NEWID()
. That command will do for you a unique identifier string like: "{B6B83A8C-F92C-4FA7-9641-631143E6056C}"... If you want to insert data into that type of field you need to use a string like that... In conclusion we can say: you need to use a string parameter type, with the GUID format, and it must be unique... Aren't there a lot of conditions!!!...
But I wrote a sample: In the following sample, you can see that I used the UUID parameter as string. You can see in the stored procedure that the parameter is of uniqueidentifier
type.
CADOParameter pParamRet(CADORecordset::typeInteger, sizeof(int),
CADOParameter::paramReturnValue);
CADOParameter pParamInChar(CADORecordset::typeChar, sizeof(char) * 40,
CADOParameter::paramInput);
CADOParameter pParamID(CADORecordset::typeInteger, sizeof(int));
CString strUUID = CString("{B6B83A8C-F92C-4FA7-9641-631143E6056C}");
pParamInChar.SetValue(strUUID);
pParamID.SetValue(1);
CADOCommand pCmd(&m_pDB, "sp_UUIDTest");
pCmd.AddParameter(&pParamRet);
pCmd.AddParameter(&pParamInChar);
pCmd.AddParameter(&pParamID);
if(pRs.Execute(&pCmd))
{
int nVal = 0;
pParamRet.GetValue(nVal);
}
//SQL SCRIPT
Create Procedure sp_UUIDTest
@UUID uniqueidentifier = NULL,
@ID integer
AS
UPDATE
systable01
SET
UUID = @UUID
WHERE
sysfield00 = @ID
if @@Error = 0
return 1
else
return 99
GO
ADO and ADOX together
I receive several emails per day asking me how I can use the ADO and ADOX classes together. The answer is, right now, from version 2.10 of ADO, you can use the two types of classes together. For this, you must include the headers and CPP files of each class and then must include the headers in the project.
Remarks
It's very important to verify that the includes must be in the following order. First the ADOX classes header and then the ADO classes header.
#include <adox.h>
#include <ado2.h>
Carlos A. Antollini.
Updates
Special thanks
These classes received many suggestions from the users. Thanks to all for your collaboration.
- Rainer Mangold
- Christian Graus
- Mike Osbahr
- Francis BONTHOUX
- Spiros Prantalos
- Robert Pittenger
- Giles Forster
- Rob Sandhu
- Marcel Stoica
- Daniel Berman
- Jan Stocker
- And tons of people requesting for new versions.