Den
Fri Apr 13 01:40:01 CDT 2007
Thanks Anders!!
"Anders Altberg" <anders.altberg> wrote in message
news:eAoQz0CfHHA.4128@TK2MSFTNGP05.phx.gbl...
> Hi Den
> ODBC and OLE DB are two different sets of commands and functions as
> drivers for connections to client/server SQL databases. In VFP these are
> called 'remote databases'.
> ODBC is an industry standard supported by Microsoft; OLE DB is a Microsoft
> Windows specific rival technology.
> MS thought their OLEDB classes would make ODBC obsolete but they have had
> second thoughts and will continue to fully support their own RDBMS product
> "SQL Server" with an powerful and fully featured ODBC driver. Windows
> also comes with an ODBC driver for MSAccess and Oracle databases. They are
> distributed and updated with the MDAC package.
> The ODBC driver for FoxPro databases was dropped in VFP7 and replaced with
> an OLEDB provider.
>
> OLEDB is a set of COM classes, ODBC uses C functions.
> That's why OLEDB is initialized with CREATEOBJECT() calls such as
> o1 = CreateObject('ADODB.Connection')
> o2 = CreateObject('ADODB.Command')
> o3 = CreateObject('ADODB.RecordSet')
> o4 = CreateObject('ADOX.Catalog')
>
> Visual FoxPro has functionality for using ODBC built into 14 functions
> that all begin with the letters SQL..., like SQLSTRINGCONNECT(), SQLEXE(),
> SQLPREPARE() and so on.
> The 'remote view' functionality built into VFP databases, the Database
> Designer, the View Designer and CREATE CONNECTION and the Connection
> Designer are all wrappers for this technology.
>
> The connections strings used for ODBC and OLEDB are purposely quite
> different using different keywords for what is essentially the 'same
> thing'.
>
> OLEDB permits calling ODBC drivers but this is now a deprecated usage as
> far as Microsofts own ODBC drivers is concerned. Initializing OLEDB with
> VFP's SQLCONNECT() is just not possible at all.
>
> VFP's CursorAdapter class is intended to support OLEDB.
> Still I would say ODBC is by far the less complex and fastest route for
> VFP programmers to handle remote databases.
> Calls like SQLEXEC(connection, "SELECT query"), SQLTABLES() and
> SQLCOLUMNS() ,and USE remote_view, all return their results directly in
> the form of a VFP cursor.
> OLEDB returns an ADO RecordSet object that you have to turn into a cursor
> with CursorAdapter.CursorFill method.
>
> The special driver for ODBC to SQL Server 2005, including the Express
> editiion, is called 'SQL Native Client'. The SQL Server Compact Edition
> (CE/Mobile/Everywhere, the name varies) only comes with OLEDB drivers.
> SQL Native Client supports everything in SQL Server except XML I believe.
>
> -Anders
>
>
>
>
>
>
>
> "Den" <test@gromro.com> wrote in message
> news:ugAHuDAfHHA.596@TK2MSFTNGP06.phx.gbl...
>> sorry for not stating my question more specific.
>>
>> i'm trying to know the key benefit of these 2 method..
>> Q1- in what situation are best using SQLStringConnect and when is best to
>> use ADO?
>> Q2- In term of data fetching & updating, which method can perform
>> better.?
>> Q3- when you say SQLStringConnect can only specify ODBC driver,
>> but what is the benefit of accessing OLEDB directly over ODBC ?
>>
>> Thanks for your info and patient.
>>
>>
>>
>> "Anders Altberg" <anders.altberg> wrote in message
>> news:egRiYw0eHHA.3960@TK2MSFTNGP02.phx.gbl...
>>> And I was trying to answer that question! I'll have to do better it
>>> seems.
>>> -Anders
>>>
>>> "Den" <test@gromro.com> wrote in message
>>> news:eK7iA3xeHHA.2376@TK2MSFTNGP04.phx.gbl...
>>>> sorry, i was try to ask whats the different between fetching data using
>>>> SQLStringConnect and ADO.
>>>>
>>>>
>>>> "Anders Altberg" <anders.altberg> wrote in message
>>>> news:e$6m9doeHHA.4916@TK2MSFTNGP06.phx.gbl...
>>>>> VFP's SQLStringConnect function can only specify a ODBC driver in the
>>>>> DRIVER parameter.
>>>>> If you want to use ADODB you use the ConnectionString property of the
>>>>> Connection class.
>>>>> This string can refer to OLEDB drivers or ODBC drivers. You then
>>>>> create a RecordSet object, sometimes by way of a Command object. VFP
>>>>> has the CursorAdapter class for turning a RecordSet into a cursor
>>>>> before you can work normally with a query result in VFP.
>>>>> That's more work than getting a cursor in step 1 as we do with queries
>>>>> through ODBC.
>>>>> -Anders
>>>>>
>>>>> "Den" <test@gromro.com> wrote in message
>>>>> news:Op4swhneHHA.3960@TK2MSFTNGP02.phx.gbl...
>>>>>> what's the different of fetching data using SQLStringConnect() with
>>>>>> ADO ?
>>>>>> what the pros and cons ? and speed different.?
>>>>>>
>>>>>> Thanks!>
>>>>>
>>>>>
>>>>
>>>>
>>>
>>>
>>
>>
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>