Использование улучшенных функций даты и времени (OLE DB)
Применимо к:
SQL Server База данных SQL Azure Управляемый экземпляр SQL Azure Azure Synapse Analytics AnalyticsPlatform System (PDW)
В этом примере показано, как использовать функции даты и времени, представленные в SQL Server 2008 (10.0.x). В образце используются четыре новых типа даты и времени (date, time, datetime2и datetimeoffset) для выполнения команд с параметрами и получения результирующих наборов строк.
Примеры кода Transact-SQL в этой статье используют AdventureWorks2022 пример базы данных, которую можно скачать на домашней странице примеров и проектов сообщества Microsoft SQL Server.
Внимание
По возможности используйте аутентификацию Windows. Если проверка подлинности Windows недоступна, запросите у пользователя ввод учетных данных во время выполнения. Избегайте хранения учетных данных в файле. Если необходимо сохранить учетные данные, зашифруйте их с помощью API-интерфейса шифрования Win32.
Пример
Первый листинг кода (Transact-SQL) создает хранимую процедуру, которая используется в примере.
Выполните компиляцию с библиотеками ole32.lib и oleaut32.lib, а затем выполните второй листинг кода (C++). Это приложение подключается к экземпляру SQL Server по умолчанию компьютера. В некоторых операционных системах Windows необходимо изменить (localhost) или (local) имя экземпляра SQL Server. Чтобы подключиться к именованным экземплярам, измените строка подключения с L"(local)" на L"(local)\name", где имя — именованный экземпляр. По умолчанию SQL Server Express устанавливает в именованный экземпляр. Убедитесь в том, что переменная среды INCLUDE включает каталог, содержащий файл msoledbsql.h.
Третий листинг кода (Transact-SQL) удаляет хранимую процедуру, используемую в примере.
CREATE PROCEDURE sp_datetimetypes
@date_param DATE OUTPUT,
@time_param TIME(7) OUTPUT,
@datetime2_param DATETIME2(7) OUTPUT,
@datetimeoffset_param DATETIMEOFFSET(7) OUTPUT
AS
SELECT @date_param, @time_param, @datetime2_param, @datetimeoffset_param
GO
// compile with: ole32.lib oleaut32.lib
#define WIN32_LEAN_AND_MEAN
#include <stdio.h>
#include <tchar.h>
#include <msoledbsql.h>
#include "oledberr.h"
#include <stddef.h>
static const DBLENGTH sc_cchStrLen = 64;
struct DateTimeTypeEx {
DBSTATUS status;
DBLENGTH length;
union {
DBTIMESTAMP ts;
DBDATE d;
DBTIME2 t;
DBTIMESTAMPOFFSET tso;
WCHAR wstr[sc_cchStrLen];
CHAR str[sc_cchStrLen];
};
};
struct TypePrecScalEx {
DBTYPE wType;
BYTE bPrec;
BYTE bScale;
WCHAR wszTypeName[64];
DBLENGTH ulSize;
};
HRESULT InitializeAndEstablishConnection (IUnknown ** ppUnkDBInitialize) {
HRESULT hr = S_OK;
IDBProperties * pIDBProperties = NULL;
IDBInitialize * pIDBInitialize = NULL;
DBPROPSET rgInitPropSet[1] = {0};
DBPROP InitProperties[4] = {0};
*ppUnkDBInitialize = NULL;
// Initialize the COM library.
CoInitialize(NULL);
// Obtain access to the OLE DB Driver for SQL Server.
hr = CoCreateInstance(CLSID_MSOLEDBSQL, NULL, CLSCTX_INPROC_SERVER, IID_IDBInitialize, (void **) &pIDBInitialize);
// Initialize property values needed to establish connection.
for (unsigned int i = 0 ; i < 4 ; i++)
VariantInit(&InitProperties[i].vValue);
// Server name.
// See DBPROP structure for more information on InitProperties
InitProperties[0].dwPropertyID = DBPROP_INIT_DATASOURCE;
InitProperties[0].vValue.vt = VT_BSTR;
InitProperties[0].vValue.bstrVal= SysAllocString(L"localhost");
InitProperties[0].dwOptions = DBPROPOPTIONS_REQUIRED;
InitProperties[0].colid = DB_NULLID;
// Database.
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;
// Username (login).
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;
InitProperties[3].dwOptions = DBPROPOPTIONS_REQUIRED;
InitProperties[3].colid = DB_NULLID;
// Construct the DBPROPSET structure(rgInitPropSet). The DBPROPSET structure is used to pass
// an array of DBPROP structures (InitProperties) to the 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);
hr = pIDBProperties->SetProperties(1, rgInitPropSet);
pIDBProperties->Release();
// Establish the connection to the data source.
hr = pIDBInitialize->Initialize();
if (S_OK == hr)
*ppUnkDBInitialize = pIDBInitialize;
return hr;
}
// This function creates an OLE DB Session object from the given DataSource object.
HRESULT myCreateSession(IUnknown * pUnkDataSource, REFIID riid, IUnknown ** ppUnkSession) {
HRESULT hr;
IDBCreateSession * pIDBCreateSession = NULL;
// Create a session object from a data source object
hr = pUnkDataSource->QueryInterface(IID_IDBCreateSession, (void**)&pIDBCreateSession);
hr = pIDBCreateSession->CreateSession(NULL, riid, ppUnkSession);
if (pIDBCreateSession)
pIDBCreateSession->Release();
return hr;
}
// This function takes an IUnknown pointer on a Session object and attempts to create a Command object
// object using the Session's IDBCreateCommand interface. Since this interface is optional, this may fail.
HRESULT myCreateCommand(IUnknown * pUnkSession, IUnknown ** ppUnkCommand) {
HRESULT hr;
IDBCreateCommand * pIDBCreateCommand = NULL;
// Attempt to create a Command object from the Session object
hr = pUnkSession->QueryInterface(IID_IDBCreateCommand, (void**)&pIDBCreateCommand);
hr = pIDBCreateCommand->CreateCommand(NULL, IID_ISSCommandWithParameters, ppUnkCommand);
if (pIDBCreateCommand)
pIDBCreateCommand->Release();
return hr;
}
// This function takes an IUnknown pointer on a Command object and creates a new Rowset object as follows:
// * Sets the given properties on the Command object. These properties will be
// applied by the provider to any Rowset created by this Command.
// * Sets the given command text for the Command.
// * Executes the command to create a new Rowset object.
HRESULT myExecuteCommand(ISSCommandWithParameters * pUnkCommand, ULONG cPropSets, DBPROPSET* rgPropSets, IUnknown ** ppUnkRowset) {
HRESULT hr;
ICommandText * pICommandText = NULL;
ICommandProperties * pICommandProperties = NULL;
IAccessor * pIAccessor = NULL;
IAccessor * pIAccessorRowset = NULL;
HACCESSOR hAccessor = NULL;
HACCESSOR hAccessorWstr = NULL;
DBCOUNTITEM cRowsObtained = 0;
HROW * rghRow = NULL;
static const DBCOUNTITEM sc_cCol = 4;
static const DB_UPARAMS sc_cParams = sc_cCol;
static const DBROWCOUNT sc_cRows = 1;
// Bindings and values
DateTimeTypeEx rgDttEx[sc_cCol] = {0};
DBBINDING rgBindings[sc_cCol] = {0};
DBBINDSTATUS rgStatus[sc_cCol] = {0};
DBBINDING rgBindingsWstr[sc_cCol] = {0};
TypePrecScalEx rgTpsEx[sc_cCol] = {
DBTYPE_DBDATE, 0, 0, L"DATE", sizeof(DBDATE),
DBTYPE_DBTIME2, 0, 4, L"TIME", sizeof(DBTIME2),
DBTYPE_DBTIMESTAMP, 0, 4, L"DATETIME2", sizeof(DBTIMESTAMP),
DBTYPE_DBTIMESTAMPOFFSET, 0, 4, L"DATETIMEOFFSET", sizeof(DBTIMESTAMPOFFSET)
};
// Command, bindings, and param values
WCHAR * pwszCommandText = L"{call sp_datetimetypes(?,?,?,?)}";
DB_UPARAMS rgParamOrdinals[sc_cParams] = {0};
DBPARAMBINDINFO rgParamBindInfo[sc_cParams] = {0};
DBPARAMS myDBPARAMS = {0};
// Set param ordinals
for (unsigned int i = 0; i < sc_cParams; i++)
rgParamOrdinals[i] = i + 1;
// Set param bind info
for (unsigned int i = 0; i < sc_cParams; i++) {
rgParamBindInfo[i].pwszDataSourceType = rgTpsEx[i].wszTypeName;
rgParamBindInfo[i].bPrecision = rgTpsEx[i].bPrec;
rgParamBindInfo[i].bScale = rgTpsEx[i].bScale;
rgParamBindInfo[i].dwFlags = DBPARAMFLAGS_ISINPUT | DBPARAMFLAGS_ISOUTPUT | DBPARAMFLAGS_ISNULLABLE;
rgParamBindInfo[i].pwszName = NULL;
rgParamBindInfo[i].ulParamSize = rgTpsEx[i].ulSize;
}
// Prepare bindings
for (unsigned int i = 0; i < sc_cParams; i++) {
rgBindings[i].iOrdinal = i+1;
rgBindings[i].obValue = (i * sizeof(DateTimeTypeEx)) + offsetof(DateTimeTypeEx, t);
rgBindings[i].obLength = (i * sizeof(DateTimeTypeEx)) + offsetof(DateTimeTypeEx, length);
rgBindings[i].obStatus = (i * sizeof(DateTimeTypeEx));
rgBindings[i].pTypeInfo = NULL;
// rgBindings[i].pObject not used
rgBindings[i].pBindExt = NULL;
rgBindings[i].dwPart = DBPART_VALUE | DBPART_LENGTH | DBPART_STATUS;
rgBindings[i].dwMemOwner = DBMEMOWNER_CLIENTOWNED;
rgBindings[i].eParamIO = DBPARAMIO_INPUT | DBPARAMIO_OUTPUT;
rgBindings[i].cbMaxLen = 0; // ignored for fixed length types
rgBindings[i].dwFlags = 0;
rgBindings[i].wType = rgTpsEx[i].wType;
rgBindings[i].bPrecision = rgTpsEx[i].bPrec;
rgBindings[i].bScale = rgTpsEx[i].bScale;
rgBindingsWstr[i].iOrdinal = i+1;
rgBindingsWstr[i].obValue = (i * sizeof(DateTimeTypeEx)) + offsetof(DateTimeTypeEx, t);
rgBindingsWstr[i].obLength = (i * sizeof(DateTimeTypeEx)) + offsetof(DateTimeTypeEx, length);
rgBindingsWstr[i].obStatus = (i * sizeof(DateTimeTypeEx));
rgBindingsWstr[i].pTypeInfo = NULL;
// rgBindingsWstr[i].pObject not used
rgBindingsWstr[i].pBindExt = NULL;
rgBindingsWstr[i].dwPart = DBPART_VALUE | DBPART_LENGTH | DBPART_STATUS;
rgBindingsWstr[i].dwMemOwner = DBMEMOWNER_CLIENTOWNED;
rgBindingsWstr[i].eParamIO = DBPARAMIO_NOTPARAM ;
rgBindingsWstr[i].cbMaxLen = sizeof(WCHAR)*sc_cchStrLen;
rgBindingsWstr[i].dwFlags = 0;
rgBindingsWstr[i].wType = DBTYPE_WSTR;
rgBindingsWstr[i].bPrecision = 0;
rgBindingsWstr[i].bScale = 0;
}
// Create accessors
hr = pUnkCommand->QueryInterface(IID_IAccessor, (void**)&pIAccessor);
hr = pIAccessor->CreateAccessor (DBACCESSOR_PARAMETERDATA, sc_cCol, rgBindings, 0, &hAccessor, rgStatus);
myDBPARAMS.cParamSets = 1;
myDBPARAMS.pData = rgDttEx;
myDBPARAMS.hAccessor = hAccessor;
// Set the properties on the Command object
hr = pUnkCommand->QueryInterface(IID_ICommandProperties, (void**)&pICommandProperties);
hr = pICommandProperties->SetProperties(cPropSets, rgPropSets);
// Set the text for this Command, using the default command text
// dialect. All providers that support commands must support this
// dialect and providers that support SQL must be able to recognize
// an SQL command as SQL when this dialect is specified
hr = pUnkCommand->QueryInterface(IID_ICommandText, (void**)&pICommandText);
hr = pICommandText->SetCommandText(DBGUID_DEFAULT, pwszCommandText);
// Set value in preparation for executing command
rgDttEx[0].length = sizeof(DBDATE);
rgDttEx[0].d.year = 1979;
rgDttEx[0].d.month = 4;
rgDttEx[0].d.day = 1;
rgDttEx[1].length = sizeof(DBTIME2);
rgDttEx[1].t.hour = 2;
rgDttEx[1].t.minute = 3;
rgDttEx[1].t.second = 5;
rgDttEx[1].t.fraction = 800000;
rgDttEx[2].length = sizeof(DBTIMESTAMP);
rgDttEx[2].ts.year = 1776;
rgDttEx[2].ts.month = 7;
rgDttEx[2].ts.day = 4;
rgDttEx[2].ts.hour = 21;
rgDttEx[2].ts.minute = 39;
rgDttEx[2].ts.second = 59;
rgDttEx[2].ts.fraction = 5000000;
rgDttEx[3].length = sizeof(DBTIMESTAMPOFFSET);
rgDttEx[3].tso.year = 1979;
rgDttEx[3].tso.month = 4;
rgDttEx[3].tso.day = 1;
rgDttEx[3].tso.hour = 2;
rgDttEx[3].tso.minute = 3;
rgDttEx[3].tso.second = 5;
rgDttEx[3].tso.fraction = 0;
rgDttEx[3].tso.timezone_hour = -5;
rgDttEx[3].tso.timezone_minute = 0;
// Add parameter info
hr = pUnkCommand->SetParameterInfo(sc_cParams, rgParamOrdinals, rgParamBindInfo);
// Execute the Command. User could enter a non-row returning command, so we check for
// that and return failure to prevent the display of the non-existant rowset by the caller
hr = pICommandText->Execute(NULL, IID_IRowset, &myDBPARAMS, NULL, ppUnkRowset);
if (FAILED(hr) || !*ppUnkRowset) {
printf("\nThe command executed, but did not " \
"return a rowset.\nNo rowset will be displayed.\n");
hr = E_FAIL;
// exit(0);
}
else
{
// Create accessor for rowset
hr = (*ppUnkRowset)->QueryInterface(IID_IAccessor, (void**)&pIAccessorRowset);
hr = pIAccessorRowset->CreateAccessor (DBACCESSOR_ROWDATA, sc_cCol, rgBindingsWstr, 0, &hAccessorWstr, rgStatus);
hr = ((IRowset*)*ppUnkRowset)->GetNextRows(DB_NULL_HCHAPTER, 0, sc_cRows, &cRowsObtained, &rghRow);
hr = ((IRowset*)*ppUnkRowset)->GetData(rghRow[0], hAccessorWstr, rgDttEx);
printf ("Data returned from sp_datetimetypes -------------\n%32ls%32ls%32ls%32ls\n",
rgDttEx[0].wstr, rgDttEx[1].wstr, rgDttEx[2].wstr, rgDttEx[3].wstr);
}
if (pICommandText)
pICommandText->Release();
if (pICommandProperties)
pICommandProperties->Release();
if (pIAccessor)
pIAccessor->Release();
if (pIAccessorRowset)
pIAccessorRowset->Release();
return hr;
}
HRESULT myTableDefinition (IUnknown * pUnkDataSource, DBID * pTableID, IUnknown ** ppUnkRowset) {
HRESULT hr;
ITableDefinition * pITableDefinition = NULL;
HACCESSOR hAccessor = NULL;
static const DBORDINAL sc_cCol = 4;
DBCOLUMNDESC rgColumnDescs[sc_cCol];
pTableID->eKind = DBKIND_NAME;
pTableID->uName.pwszName = L"datetimetypestable";
rgColumnDescs[0].pwszTypeName = L"date";
rgColumnDescs[0].pTypeInfo = NULL;
rgColumnDescs[0].rgPropertySets = NULL;
rgColumnDescs[0].pclsid = NULL;
rgColumnDescs[0].cPropertySets = 0;
rgColumnDescs[0].ulColumnSize = 0;
rgColumnDescs[0].dbcid.eKind = DBKIND_NAME;
rgColumnDescs[0].dbcid.uName.pwszName = L"datecol";
rgColumnDescs[0].wType = DBTYPE_DBDATE;
rgColumnDescs[0].bPrecision = 0;
rgColumnDescs[0].bScale = 0;
rgColumnDescs[1].pwszTypeName = L"time";
rgColumnDescs[1].pTypeInfo = NULL;
rgColumnDescs[1].rgPropertySets = NULL;
rgColumnDescs[1].pclsid = NULL;
rgColumnDescs[1].cPropertySets = 0;
rgColumnDescs[1].ulColumnSize = 0;
rgColumnDescs[1].dbcid.eKind = DBKIND_NAME;
rgColumnDescs[1].dbcid.uName.pwszName = L"timecol";
rgColumnDescs[1].wType = DBTYPE_DBTIME2;
rgColumnDescs[1].bPrecision = 0;
rgColumnDescs[1].bScale = 7;
rgColumnDescs[2].pwszTypeName = L"datetime2";
rgColumnDescs[2].pTypeInfo = NULL;
rgColumnDescs[2].rgPropertySets = NULL;
rgColumnDescs[2].pclsid = NULL;
rgColumnDescs[2].cPropertySets = 0;
rgColumnDescs[2].ulColumnSize = 0;
rgColumnDescs[2].dbcid.eKind = DBKIND_NAME;
rgColumnDescs[2].dbcid.uName.pwszName = L"datetime2col";
rgColumnDescs[2].wType = DBTYPE_DBTIMESTAMP;
rgColumnDescs[2].bPrecision = 0;
rgColumnDescs[2].bScale = 7;
rgColumnDescs[3].pwszTypeName = L"datetimeoffset";
rgColumnDescs[3].pTypeInfo = NULL;
rgColumnDescs[3].rgPropertySets = NULL;
rgColumnDescs[3].pclsid = NULL;
rgColumnDescs[3].cPropertySets = 0;
rgColumnDescs[3].ulColumnSize = 0;
rgColumnDescs[3].dbcid.eKind = DBKIND_NAME;
rgColumnDescs[3].dbcid.uName.pwszName = L"datetimeoffsetcol";
rgColumnDescs[3].wType = DBTYPE_DBTIMESTAMPOFFSET;
rgColumnDescs[3].bPrecision = 0;
rgColumnDescs[3].bScale = 7;
hr = pUnkDataSource->QueryInterface(IID_ITableDefinition, (void**)&pITableDefinition);
hr = pITableDefinition->CreateTable(NULL, pTableID, sc_cCol, rgColumnDescs, IID_IRowset, 0, NULL, &pTableID, ppUnkRowset);
// Ignore the case where the table already exists
if (DB_E_DUPLICATETABLEID == hr)
hr = S_OK;
if (pITableDefinition)
pITableDefinition->Release();
return hr;
}
HRESULT myTableChange(IOpenRowset * pIOpenRowset, DBID * pTableID, IUnknown ** ppUnkRowset) {
HRESULT hr;
IRowsetChange * pIRowsetChange = NULL;
IAccessor * pIAccessor = NULL;
HACCESSOR hAccessor = NULL;
HROW hRow = NULL;
static const DBCOUNTITEM sc_cCol = 4;
// Bindings and values
DateTimeTypeEx rgDttEx[sc_cCol] = {0};
DBBINDING rgBindings[sc_cCol] = {0};
DBBINDSTATUS rgStatus[sc_cCol] = {0};
TypePrecScalEx rgTpsEx[sc_cCol] = {
DBTYPE_DBDATE, 0, 0, L"DATE", sizeof(DBDATE),
DBTYPE_DBTIME2, 0, 7, L"TIME", sizeof(DBTIME2),
DBTYPE_DBTIMESTAMP, 0, 7, L"DATETIME2", sizeof(DBTIMESTAMP),
DBTYPE_DBTIMESTAMPOFFSET, 0, 7, L"DATETIMEOFFSET", sizeof(DBTIMESTAMPOFFSET)
};
// Open IRowsetChange interface on existing table
hr = pIOpenRowset->OpenRowset(NULL, pTableID, NULL, IID_IRowsetChange, 0, NULL, (IUnknown**)&pIRowsetChange);
// Prepare bindings
for (unsigned int i = 0; i < sc_cCol; i++) {
rgBindings[i].iOrdinal = i+1;
rgBindings[i].obValue = (i * sizeof(DateTimeTypeEx)) + offsetof(DateTimeTypeEx, t);
rgBindings[i].obLength = (i * sizeof(DateTimeTypeEx)) + offsetof(DateTimeTypeEx, length);
rgBindings[i].obStatus = (i * sizeof(DateTimeTypeEx));
rgBindings[i].pTypeInfo = NULL;
// rgBindings[i].pObject not used
rgBindings[i].pBindExt = NULL;
rgBindings[i].dwPart = DBPART_VALUE | DBPART_LENGTH | DBPART_STATUS;
rgBindings[i].dwMemOwner = DBMEMOWNER_CLIENTOWNED;
rgBindings[i].eParamIO = DBPARAMIO_NOTPARAM ;
rgBindings[i].cbMaxLen = 0; // ignored for fixed length types (sizeof(DBTIMESTAMP))
rgBindings[i].dwFlags = 0;
rgBindings[i].wType = rgTpsEx[i].wType;
rgBindings[i].bPrecision = rgTpsEx[i].bPrec;
rgBindings[i].bScale = rgTpsEx[i].bScale;
}
// Create accessors
hr = pIRowsetChange->QueryInterface(IID_IAccessor, (void**)&pIAccessor);
hr = pIAccessor->CreateAccessor (DBACCESSOR_ROWDATA, sc_cCol, rgBindings, 0, &hAccessor, rgStatus);
// Set value in preparation for inserting a new row
rgDttEx[0].length = sizeof(DBDATE);
rgDttEx[0].d.year = 1979;
rgDttEx[0].d.month = 4;
rgDttEx[0].d.day = 1;
rgDttEx[1].length = sizeof(DBTIME2);
rgDttEx[1].t.hour = 2;
rgDttEx[1].t.minute = 3;
rgDttEx[1].t.second = 5;
rgDttEx[1].t.fraction = 800000;
rgDttEx[2].length = sizeof(DBTIMESTAMP);
rgDttEx[2].ts.year = 1776;
rgDttEx[2].ts.month = 7;
rgDttEx[2].ts.day = 4;
rgDttEx[2].ts.hour = 21;
rgDttEx[2].ts.minute = 39;
rgDttEx[2].ts.second = 59;
rgDttEx[2].ts.fraction = 5000000;
rgDttEx[3].length = sizeof(DBTIMESTAMPOFFSET);
rgDttEx[3].tso.year = 1979;
rgDttEx[3].tso.month = 4;
rgDttEx[3].tso.day = 1;
rgDttEx[3].tso.hour = 2;
rgDttEx[3].tso.minute = 3;
rgDttEx[3].tso.second = 5;
rgDttEx[3].tso.fraction = 0;
rgDttEx[3].tso.timezone_hour = -5;
rgDttEx[3].tso.timezone_minute = 0;
hr = pIRowsetChange->InsertRow(NULL, hAccessor, rgDttEx, &hRow);
if (pIRowsetChange)
pIRowsetChange->Release();
if (pIAccessor)
pIAccessor->Release();
return hr;
}
HRESULT myTableRead(IOpenRowset * pIOpenRowset, DBID * pTableID, IUnknown ** ppUnkRowset) {
HRESULT hr;
IRowset * pIRowset = NULL;
IAccessor * pIAccessor = NULL;
HACCESSOR hAccessor = NULL;
HACCESSOR hAccessorStr = NULL;
HACCESSOR hAccessorWstr = NULL;
static const DBROWCOUNT sc_cRows = 1;
HROW * rghRow = NULL;
DBCOUNTITEM cRowsObtained = 0;
// static const DBORDINAL sc_cCol = 4;
static const DBCOUNTITEM sc_cCol = 4;
// Bindings and values
DateTimeTypeEx rgDttEx[sc_cCol] = {0};
DBBINDING rgBindings[sc_cCol] = {0};
DBBINDSTATUS rgStatus[sc_cCol] = {0};
DBBINDING rgBindingsStr[sc_cCol] = {0};
DBBINDING rgBindingsWstr[sc_cCol] = {0};
TypePrecScalEx rgTpsEx[sc_cCol] = {
DBTYPE_DBDATE, 0, 0, L"DATE", sizeof(DBDATE),
DBTYPE_DBTIME2, 0, 0, L"TIME", sizeof(DBTIME2),
DBTYPE_DBTIMESTAMP, 0, 0, L"DATETIME2", sizeof(DBTIMESTAMP),
DBTYPE_DBTIMESTAMPOFFSET, 0, 0, L"DATETIMEOFFSET", sizeof(DBTIMESTAMPOFFSET)
};
printf ("%d = sizeof(DateTimeTypeEx)\n", sizeof(DateTimeTypeEx));
// Open IRowsetChange interface on existing table
hr = pIOpenRowset->OpenRowset(NULL, pTableID, NULL, IID_IRowset, 0, NULL, (IUnknown**)&pIRowset);
// Prepare bindings
for (unsigned int i = 0; i < 4; i++) {
rgBindings[i].iOrdinal = i+1;
rgBindingsStr[i].iOrdinal = i+1;
rgBindingsWstr[i].iOrdinal = i+1;
rgBindings[i].obValue = (i * sizeof(DateTimeTypeEx)) + offsetof(DateTimeTypeEx, t);
rgBindings[i].obLength = (i * sizeof(DateTimeTypeEx)) + offsetof(DateTimeTypeEx, length);
rgBindingsStr[i].obValue = (i * sizeof(DateTimeTypeEx)) + offsetof(DateTimeTypeEx, t);
rgBindingsWstr[i].obValue = (i * sizeof(DateTimeTypeEx)) + offsetof(DateTimeTypeEx, t);;
rgBindings[i].obLength = (i * sizeof(DateTimeTypeEx)) + offsetof(DateTimeTypeEx, length);
rgBindingsStr[i].obLength = (i * sizeof(DateTimeTypeEx)) + offsetof(DateTimeTypeEx, length);
rgBindingsWstr[i].obLength = (i * sizeof(DateTimeTypeEx)) + offsetof(DateTimeTypeEx, length);
rgBindings[i].obStatus = (i * sizeof(DateTimeTypeEx));
rgBindingsStr[i].obStatus = (i * sizeof(DateTimeTypeEx));
rgBindingsWstr[i].obStatus = (i * sizeof(DateTimeTypeEx));
rgBindings[i].pTypeInfo = NULL;
rgBindingsStr[i].pTypeInfo = NULL;
rgBindingsWstr[i].pTypeInfo = NULL;
// rgBindings[i].pObject not used
rgBindings[i].pBindExt = NULL;
rgBindingsStr[i].pBindExt = NULL;
rgBindingsWstr[i].pBindExt = NULL;
rgBindings[i].dwPart = DBPART_VALUE | DBPART_LENGTH | DBPART_STATUS;
rgBindingsStr[i].dwPart = DBPART_VALUE | DBPART_LENGTH | DBPART_STATUS;
rgBindingsWstr[i].dwPart = DBPART_VALUE | DBPART_LENGTH | DBPART_STATUS;
rgBindings[i].dwMemOwner = DBMEMOWNER_CLIENTOWNED;
rgBindingsStr[i].dwMemOwner = DBMEMOWNER_CLIENTOWNED;
rgBindingsWstr[i].dwMemOwner = DBMEMOWNER_CLIENTOWNED;
rgBindings[i].eParamIO = DBPARAMIO_NOTPARAM ;
rgBindingsStr[i].eParamIO = DBPARAMIO_NOTPARAM ;
rgBindingsWstr[i].eParamIO = DBPARAMIO_NOTPARAM ;
rgBindings[i].cbMaxLen = 0; // ignored for fixed length types
rgBindingsStr[i].cbMaxLen = sc_cchStrLen;
rgBindingsWstr[i].cbMaxLen = sizeof(WCHAR)*sc_cchStrLen;
rgBindings[i].dwFlags = 0;
rgBindingsStr[i].dwFlags = 0;
rgBindingsWstr[i].dwFlags = 0;
rgBindings[i].wType = rgTpsEx[i].wType;
rgBindingsStr[i].wType = DBTYPE_STR;
rgBindingsWstr[i].wType = DBTYPE_WSTR;
rgBindings[i].bPrecision = rgTpsEx[i].bPrec;
rgBindingsStr[i].bPrecision = 0;
rgBindingsWstr[i].bPrecision = 0;
rgBindings[i].bScale = rgTpsEx[i].bScale;
rgBindingsStr[i].bScale = 0;
rgBindingsWstr[i].bScale = 0;
}
// Create accessors
hr = pIRowset->QueryInterface(IID_IAccessor, (void**)&pIAccessor);
hr = pIAccessor->CreateAccessor (DBACCESSOR_ROWDATA, sc_cCol, rgBindings, 0, &hAccessor, rgStatus);
hr = pIAccessor->CreateAccessor (DBACCESSOR_ROWDATA, sc_cCol, rgBindingsStr, 0, &hAccessorStr, rgStatus);
hr = pIAccessor->CreateAccessor (DBACCESSOR_ROWDATA, sc_cCol, rgBindingsWstr, 0, &hAccessorWstr, rgStatus);
hr = pIRowset->GetNextRows(DB_NULL_HCHAPTER, 0, sc_cRows, &cRowsObtained, &rghRow);
hr = pIRowset->GetData(rghRow[0], hAccessor, rgDttEx);
hr = pIRowset->GetData(rghRow[0], hAccessorStr, rgDttEx);
hr = pIRowset->GetData(rghRow[0], hAccessorWstr, rgDttEx);
if (pIRowset)
pIRowset->Release();
if (pIAccessor)
pIAccessor->Release();
return hr;
}
int main() {
HRESULT hr = S_OK;
IDBInitialize * pIDBInitialize = NULL;
IDBCreateSession * pIDBCreateSession = NULL;
ISSCommandWithParameters * pIDBCreateCommand = NULL;
IOpenRowset * pIOpenRowset = NULL;
IRowset * pIRowset = NULL;
DBID tableID = {0};
hr = InitializeAndEstablishConnection((IUnknown**)&pIDBInitialize);
hr = myCreateSession((IUnknown*)pIDBInitialize, IID_IDBCreateCommand, (IUnknown**)&pIDBCreateSession);
hr = myTableDefinition(pIDBCreateSession, &tableID, (IUnknown**)&pIRowset);
hr = myCreateSession((IUnknown*)pIDBInitialize, IID_IOpenRowset, (IUnknown**)&pIOpenRowset);
hr = myTableChange(pIOpenRowset, &tableID, (IUnknown**)&pIRowset);
hr = myTableRead(pIOpenRowset, &tableID, (IUnknown**)&pIRowset);
hr = myCreateCommand((IUnknown*)pIDBCreateSession, (IUnknown**)&pIDBCreateCommand);
hr = myExecuteCommand(pIDBCreateCommand, 0, NULL, (IUnknown**)&pIRowset);
if (pIDBInitialize)
pIDBInitialize->Release();
if (pIDBCreateSession)
pIDBCreateSession->Release();
if (pIDBCreateCommand)
pIDBCreateCommand->Release();
if (pIRowset)
pIRowset->Release();
}
IF EXISTS (SELECT name FROM sysobjects WHERE name = 'sp_datetimetypes')
DROP PROCEDURE sp_datetimetypes
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