[fpc-pascal] TBufDataSet: ApplyUpdates

[Sven Barth]

On 03.05.2012 15:40, Marcos Douglas wrote:
> On Thu, May 3, 2012 at 10:01 AM, LacaK<lacak at zoznam.sk>  wrote:
>> Marcos Douglas  wrote / napísal(a):
>>
>> On Thu, May 3, 2012 at 2:52 AM, LacaK<lacak at zoznam.sk>  wrote:
>>
>>
>> I saw the TBufDataSet.ApplyUpdates and it calls ApplyRecUpdate.
>> The ApplyRecUpdate just raises an exception...
>>
>>
>>
>> Yes it is virtual method, which can be overriden by descendants
>>
>>
>>
>>
>> There is some implementation, in some place, to work with ApplyUpdates
>> (like a Delphi's TClientDataSet)?
>>
>>
>>
>> Yes, see in sqldb.pp at TCustomSQLQuery
>>
>>
>> Yeah... I did not know that the TCustomSQLQuery descended of
>> TCustomBufDataSet.
>> Well, I tried to use ApplyUpdates with TSQLQuery and TMSSQLConnection
>> (SQLServer).
>> I put a DBGrid, DataSource... blablabla... I edited the record on the
>> Grid and click in Apply button (ApplyUpdates(0))
>>
>> ERROR 20019:
>> "Attempt to initiate a new SQL Server operation with results pending."
>>
>> On the internet I found this:
>> http://www.sybase.com.br/detail?id=897#1825
>>
>> I don't have other SGBD now to test so, I would like to know if this
>> is a problem in TMSSQLConnection or in ApplyUpdates?
>>
>>
>>
>> Yes it is a known problem (also in ODBC), read also in
>> sqldb/mssql/readme.txt:
>> - DB-Library error 10038 "Results Pending" - set TSQLQuery.PacketRecords=-1
>> to fetch all pendings rows
>> HTH
>> -Laco.
>
> You're right, but I have others problems:
> I changed PacketRecords=-1 and test again. No errors, but didn't
> commited (I'm seeing the SQL Profiler).
> So, I used:
>    SQLQuery1.ApplyUpdates(0);
>    SQLTransaction1.Commit;
>
> Worked, using Commit, but the DataSet was closed (?)
>
> The SQLQuery properties are:
> UpdateMode = upWhereKeyOnly
> UsePrimaryKeyAsKey = True
>
> Maybe there is no problem and I just have to know how the SQLdb works.
> Could you help me on this?

If you don't want the dataset closed then you must use CommitRetaining 
(or RollbackRetaining for Rollback).

Regards,
Sven