ユーザー定義関数の実行とリターン コードの処理 (OLE DB)
この例では、ユーザー定義関数を実行して、リターン コードを出力します。 このサンプルは IA64 ではサポートされていません。
このサンプルには AdventureWorks サンプル データベースが必要です。このサンプル データベースは、Microsoft SQL Server サンプルとコミュニティのプロジェクトのホーム ページからダウンロードできます。
セキュリティに関する注意 |
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可能な場合は、Windows 認証を使用します。 Windows 認証が使用できない場合は、実行時に資格情報を入力するようユーザーに求めます。 資格情報をファイルに保存するのは避けてください。 資格情報を保存する必要がある場合は、Win32 Crypto API を使用して暗号化してください。 |
使用例
1 つ目の (Transact-SQL) コード リストを実行して、アプリケーションで使用するストアド プロシージャを作成します。
ole32.lib と oleaut32.lib を使用して 2 つ目の (C++) コード リストをコンパイルし、実行します。 このアプリケーションは、コンピューターの既定の SQL Server インスタンスに接続します。 一部の Windows オペレーティング システムでは、(localhost) または (local) を実際の SQL Server インスタンスの名前に変更する必要があります。 名前付きインスタンスに接続するには、接続文字列を L"(local)" から L"(local)\\name" に変更します。name は名前付きインスタンスです。 SQL Server Express は、既定で名前付きインスタンスとしてインストールされます。 INCLUDE 環境変数に、sqlncli.h が保存されているディレクトリが含まれていることを確認します。
3 つ目の (Transact-SQL) コード リストを実行して、アプリケーションで使用したストアド プロシージャを削除します。
USE AdventureWorks
if exists (SELECT * FROM sys.objects WHERE object_id = OBJECT_ID(N'[fn_RectangleArea]'))
drop function fn_RectangleArea
go
CREATE FUNCTION fn_RectangleArea
(@Width int,
@Height int )
RETURNS int
AS
BEGIN
RETURN ( @Width * @Height )
END
GO
// compile with: ole32.lib oleaut32.lib
void InitializeAndEstablishConnection();
#define UNICODE
#define DBINITCONSTANTS
#define INITGUID
#define OLEDBVER 0x0250 // to include correct interfaces
#include <windows.h>
#include <stdio.h>
#include <stddef.h>
#include <iostream>
#include <oledb.h>
#include <oledberr.h>
#include <sqlncli.h>
using namespace std;
IDBInitialize* pIDBInitialize = NULL;
IDBCreateSession* pIDBCreateSession = NULL;
IDBCreateCommand* pIDBCreateCommand = NULL;
ICommandText* pICommandText = NULL;
IRowset* pIRowset = NULL;
ICommandWithParameters* pICommandWithParams = NULL;
IAccessor* pIAccessor = NULL;
IDBProperties* pIDBProperties = NULL;
WCHAR* pStringsBuffer;
DBBINDING* pBindings;
const ULONG nInitProps = 4;
DBPROP InitProperties[nInitProps];
const ULONG nPropSet = 1;
DBPROPSET rgInitPropSet[nPropSet];
HRESULT hr;
HACCESSOR hAccessor;
const ULONG nParams = 3; // No. of parameters in the command
DBPARAMBINDINFO ParamBindInfo[nParams];
ULONG i;
ULONG cbColOffset = 0;
DB_UPARAMS ParamOrdinals[nParams];
DBROWCOUNT cNumRows = 0;
DBPARAMS Params;
// Declare array of DBBINDING structures, one for each parameter in the command
DBBINDING acDBBinding[nParams];
DBBINDSTATUS acDBBindStatus[nParams];
// The following buffer is used to store parameter values.
typedef struct tagSPROCPARAMS {
long lReturnValue;
long inParam1;
long inParam2;
} SPROCPARAMS;
int main() {
// The command to execute.
WCHAR* wCmdString = L"{? = CALL fn_RectangleArea(?, ?) }";
// WCHAR* wCmdString = L"EXEC ? = fn_RectangleVolume(?, ?)";
SPROCPARAMS sprocparams = {0,5,10};
// All the initialization stuff in a separate function.
InitializeAndEstablishConnection();
// Let us create a new session from the data source object.
if (FAILED(pIDBInitialize->QueryInterface( IID_IDBCreateSession,
(void**) &pIDBCreateSession))) {
cout << "Failed to access IDBCreateSession interface\n";
goto EXIT;
}
if ( FAILED(pIDBCreateSession->CreateSession( NULL,
IID_IDBCreateCommand,
(IUnknown**) &pIDBCreateCommand))) {
cout << "pIDBCreateSession->CreateSession failed\n";
goto EXIT;
}
// Create a Command
if (FAILED(pIDBCreateCommand->CreateCommand( NULL,
IID_ICommandText,
(IUnknown**) &pICommandText))) {
cout << "Failed to access ICommand interface\n";
goto EXIT;
}
// Set the command text.
if (FAILED(pICommandText->SetCommandText(DBGUID_DBSQL, wCmdString))) {
cout << "failed to set command text\n";
goto EXIT;
}
// Describe the command parameters (parameter name, provider specific name
// of the parameter's data type etc.) in an array of DBPARAMBINDINFO
// structures. This information is then used by SetParameterInfo().
ParamBindInfo[0].pwszDataSourceType = L"DBTYPE_I4";
ParamBindInfo[0].pwszName = NULL;
ParamBindInfo[0].ulParamSize = sizeof(long);
ParamBindInfo[0].dwFlags = DBPARAMFLAGS_ISOUTPUT;
ParamBindInfo[0].bPrecision = 11;
ParamBindInfo[0].bScale = 0;
ParamOrdinals[0] = 1;
ParamBindInfo[1].pwszDataSourceType = L"DBTYPE_I4";
ParamBindInfo[1].pwszName = NULL; // L"@inparam1";
ParamBindInfo[1].ulParamSize = sizeof(long);
ParamBindInfo[1].dwFlags = DBPARAMFLAGS_ISINPUT;
ParamBindInfo[1].bPrecision = 11;
ParamBindInfo[1].bScale = 0;
ParamOrdinals[1] = 2;
ParamBindInfo[2].pwszDataSourceType = L"DBTYPE_I4";
ParamBindInfo[2].pwszName = NULL; // L"@inparam2";
ParamBindInfo[2].ulParamSize = sizeof(long);
ParamBindInfo[2].dwFlags = DBPARAMFLAGS_ISINPUT;
ParamBindInfo[2].bPrecision = 11;
ParamBindInfo[2].bScale = 0;
ParamOrdinals[2] = 3;
// Set the parameters information.
if (FAILED(pICommandText->QueryInterface( IID_ICommandWithParameters,
(void**)&pICommandWithParams))) {
cout << "failed to obtain ICommandWithParameters\n";
goto EXIT;
}
if (FAILED(pICommandWithParams->SetParameterInfo( nParams,
ParamOrdinals,
ParamBindInfo))) {
cout << "failed in setting parameter info.(SetParameterInfo)\n";
goto EXIT;
}
// Describe the consumer buffer; initialize the array of DBBINDING structures.
// Each binding associates a single parameter to the consumer's buffer.
for ( i = 0 ; i < nParams ; i++ ) {
acDBBinding[i].obLength = 0;
acDBBinding[i].obStatus = 0;
acDBBinding[i].pTypeInfo = NULL;
acDBBinding[i].pObject = NULL;
acDBBinding[i].pBindExt = NULL;
acDBBinding[i].dwPart = DBPART_VALUE;
acDBBinding[i].dwMemOwner = DBMEMOWNER_CLIENTOWNED;
acDBBinding[i].dwFlags = 0;
acDBBinding[i].bScale = 0;
} // for
acDBBinding[0].iOrdinal = 1;
acDBBinding[0].obValue = offsetof(SPROCPARAMS, lReturnValue);
acDBBinding[0].eParamIO = DBPARAMIO_OUTPUT;
acDBBinding[0].cbMaxLen = sizeof(long);
acDBBinding[0].wType = DBTYPE_I4;
acDBBinding[0].bPrecision = 11;
acDBBinding[1].iOrdinal = 2;
acDBBinding[1].obValue = offsetof(SPROCPARAMS, inParam1);
acDBBinding[1].eParamIO = DBPARAMIO_INPUT;
acDBBinding[1].cbMaxLen = sizeof(long);
acDBBinding[1].wType = DBTYPE_I4;
acDBBinding[1].bPrecision = 11;
acDBBinding[2].iOrdinal = 3;
acDBBinding[2].obValue = offsetof(SPROCPARAMS, inParam2);
acDBBinding[2].eParamIO = DBPARAMIO_INPUT;
acDBBinding[2].cbMaxLen = sizeof(long);
acDBBinding[2].wType = DBTYPE_I4;
acDBBinding[2].bPrecision = 11;
// Let us create an accessor from the above set of bindings.
hr = pICommandWithParams->QueryInterface( IID_IAccessor, (void**)&pIAccessor);
if (FAILED(hr))
cout << "Failed to get IAccessor interface\n";
hr = pIAccessor->CreateAccessor( DBACCESSOR_PARAMETERDATA,
nParams,
acDBBinding,
sizeof(SPROCPARAMS),
&hAccessor,
acDBBindStatus);
if (FAILED(hr))
cout << "failed to create accessor for the defined parameters\n";
// Initialize DBPARAMS structure for command execution. DBPARAMS specifies the
// parameter values in the command. DBPARAMS is then passed to Execute.
Params.pData = &sprocparams;
Params.cParamSets = 1;
Params.hAccessor = hAccessor;
// Execute the command.
if (FAILED(hr = pICommandText->Execute( NULL,
IID_IRowset,
&Params,
&cNumRows,
(IUnknown **) &pIRowset))) {
cout << "failed to execute command\n";
goto EXIT;
}
printf(" Return value = %d\n", sprocparams.lReturnValue);
// Release result set without processing.
if (pIRowset != NULL)
pIRowset->Release();
// Release memory.
pIAccessor->ReleaseAccessor(hAccessor, NULL);
pIAccessor->Release();
pICommandWithParams->Release();
pICommandText->Release();
pIDBCreateCommand->Release();
pIDBCreateSession->Release();
if (FAILED(pIDBInitialize->Uninitialize()))
// Uninitialize is not required, but it fails if an interface
// has not not been released. This can be used for debugging.
cout << "Problem uninitializing\n";
pIDBInitialize->Release();
CoUninitialize();
return 0;
EXIT:
if (pIAccessor != NULL)
pIAccessor->Release();
if (pICommandWithParams != NULL)
pICommandWithParams->Release();
if (pICommandText != NULL)
pICommandText->Release();
if (pIDBCreateCommand != NULL)
pIDBCreateCommand->Release();
if (pIDBCreateSession != NULL)
pIDBCreateSession->Release();
if (pIDBInitialize != NULL)
if (FAILED(pIDBInitialize->Uninitialize()))
// Uninitialize is not required, but it fails if an interface has
// not been released. This can be used for debugging.
cout << "problem in uninitializing\n";
pIDBInitialize->Release();
CoUninitialize();
}
void InitializeAndEstablishConnection() {
// Initialize the COM library.
CoInitialize(NULL);
// Obtain access to the SQL Server native Client OLE DB provider.
hr = CoCreateInstance( CLSID_SQLNCLI11,
NULL,
CLSCTX_INPROC_SERVER,
IID_IDBInitialize,
(void **) &pIDBInitialize);
if (FAILED(hr))
cout << "Failed in CoCreateInstance()\n";
// Initialize the property values needed to establish the connection.
for ( i = 0 ; i < nInitProps ; i++ )
VariantInit(&InitProperties[i].vValue);
// Specify server name.
InitProperties[0].dwPropertyID = DBPROP_INIT_DATASOURCE;
InitProperties[0].vValue.vt = VT_BSTR;
// Replace "MySqlServer" with proper value.
InitProperties[0].vValue.bstrVal = SysAllocString(L"(local)");
InitProperties[0].dwOptions = DBPROPOPTIONS_REQUIRED;
InitProperties[0].colid = DB_NULLID;
// Specify database name.
InitProperties[1].dwPropertyID = DBPROP_INIT_CATALOG;
InitProperties[1].vValue.vt = VT_BSTR;
InitProperties[1].vValue.bstrVal = SysAllocString(L"AdventureWorks");
InitProperties[1].dwOptions = DBPROPOPTIONS_REQUIRED;
InitProperties[1].colid = DB_NULLID;
InitProperties[2].dwPropertyID = DBPROP_AUTH_INTEGRATED;
InitProperties[2].vValue.vt = VT_BSTR;
InitProperties[2].vValue.bstrVal = SysAllocString(L"SSPI");
InitProperties[2].dwOptions = DBPROPOPTIONS_REQUIRED;
InitProperties[2].colid = DB_NULLID;
// Now that properties are set, construct the DBPROPSET structure
// (rgInitPropSet). The DBPROPSET structure is used to pass an array
// of DBPROP structures (InitProperties) to SetProperties method.
rgInitPropSet[0].guidPropertySet = DBPROPSET_DBINIT;
rgInitPropSet[0].cProperties = 4;
rgInitPropSet[0].rgProperties = InitProperties;
// Set initialization properties.
hr = pIDBInitialize->QueryInterface( IID_IDBProperties, (void **)&pIDBProperties);
if (FAILED(hr))
cout << "Failed to obtain IDBProperties interface.\n";
hr = pIDBProperties->SetProperties( nPropSet, rgInitPropSet);
if (FAILED(hr))
cout << "Failed to set initialization properties\n";
pIDBProperties->Release();
// Now we establish connection to the data source.
if (FAILED(pIDBInitialize->Initialize()))
cout << "Problem in initializing\n";
}
USE AdventureWorks
drop function fn_RectangleArea
go