On Tue, Jun 26, 2012 at 11:01 AM, deltagam...@gmx.net
<deltagam...@gmx.net>wrote:
> Am 26.06.2012 16:49, schrieb Richard Hipp:
>
> On Tue, Jun 26, 2012 at 10:46 AM, deltagam...@gmx.net
>> <deltagam...@gmx.net>wrote:
>>
>> I have a c++ GUI application from where the db is read and the content is
>>> displayed in a Clistbox.
>>> Then I try to delete some rows from the sqlite3-db from the console.
>>> After rereading from within the GUI the deleted rows are still there.
>>>
>>> How is this possible ?
>>>
>>> The GUI is holding a read transaction open. Hence it sees a consistent
>> snapshot of the database from the moment in time when the transaction was
>> started. Subsequent writes to the database are ignored by the GUI until
>> it
>> closes its current transaction and starts a new one.
>>
>>
>>
>>
> How can I close the transaction , and later open a new one ?
> BTW, transaction is still open although i use a sqlite3_close(db) ?
>
> Here is the code for reading from the db. By changing within the GUI from
> tab viewevents to another tab and back again to tab viewevents, the db is
> read again and should display all changes to the db which appeared during
> that time.
>
Are you sure the db is being read again when you change tabs? Have you set
a breakpoint to verify this?
And are you sure the database has changed?
And are you certain that your command-line and your GUI are using the same
database?
>
> ==============================**==============================**==========
>
> int ReadViewEventsFormDBData()
> {
> int nRetCode = ERROR_SUCCESS;
>
> // Remove all events from array
> m_arrEvents.RemoveAll();
>
> // write events
> Event newEvent;
>
> int rc, id, total_events;
> char *sql, *sqltotal;
> char *evdate, *evtype;
> int evctr;
>
> int the_event_ctr = 0;
>
> CString datetime;
> CString datepart;
> CString timepart;
>
> sqlite3 *db;
> sqlite3_stmt *stmt;
>
> sqlite3_open("ah.db", &db);
>
> // check if table eventlog exists
> char create_sql[] = "CREATE TABLE if not exists eventlog ("
> "id INTEGER PRIMARY KEY,"
> "eventdate DATETIME default current_timestamp,"
> "eventtype TEXT,"
> "counter INTEGER"
> ")";
>
> rc = sqlite3_exec(db, create_sql, NULL, NULL, NULL);
>
> // select count(*) from eventlog
> sqltotal = "Select count(*) from eventlog";
> rc = sqlite3_prepare(db, sqltotal, strlen(sqltotal), &stmt, NULL);
> rc = sqlite3_step(stmt);
> total_events = sqlite3_column_int(stmt, 0 );
>
> // select * from eventlog
> sql = "Select id, eventdate, eventtype, counter FROM eventlog";
> sqlite3_prepare(db, sql, strlen(sql), &stmt, NULL);
>
>
> rc = sqlite3_step(stmt);
>
> while(rc == SQLITE_ROW) {
> id = sqlite3_column_int(stmt, 0 );
> //cid = sqlite3_column_int(stmt, 1 );
> evdate = (char*)sqlite3_column_text(**stmt, 1 );
> evtype = (char*)sqlite3_column_text(**stmt, 2 );
> evctr = sqlite3_column_int(stmt, 3 );
>
> datetime = evdate;
>
> datepart = datetime.Mid(0,10);
> timepart = datetime.Mid(11,5);
>
> std::cout << datepart << "\t" << timepart << std::endl;
>
> newEvent.m_nEvent = the_event_ctr;
> newEvent.m_strLastEventDate = datepart ;
> newEvent.m_strEventTime = timepart;
> newEvent.m_strEventType = evtype;
> newEvent.m_nCount = evctr;
>
> // add the new element to array
> m_arrEvents.Add(newEvent);
>
> rc = sqlite3_step(stmt);
>
> // increment eventcounter
> the_event_ctr++;
>
> } // while
>
> sqlite3_finalize(stmt);
> sqlite3_close(db);
> nRetCode = rc;
>
> return nRetCode;
>
> } // ReadViewEventsFormDBData
>
> ==============================**==============================**
> =============
>
>
> ______________________________**_________________
> sqlite-users mailing list
> sqlite-users@sqlite.org
> http://sqlite.org:8080/cgi-**bin/mailman/listinfo/sqlite-**users<http://sqlite.org:8080/cgi-bin/mailman/listinfo/sqlite-users>
>
--
D. Richard Hipp
d...@sqlite.org
_______________________________________________
sqlite-users mailing list
sqlite-users@sqlite.org
http://sqlite.org:8080/cgi-bin/mailman/listinfo/sqlite-users
