[Qt-interest] Driver not loaded...

[Alex Strickland]

On 05/04/2011 17:19, Eric Clark wrote:

> Yes it is for good reason. I have a little over 25000 rows of data being inserted into the database and it takes a really long time to do so.

No I mean that sqlite goes to *extreme* lengths to make sure your data 
is on disk and it takes a long time.

>> supports it, any or all of these may make sense for you:
>>
>>       "PRAGMA synchronous = off"
>>       "PRAGMA journal_mode = off"
>>       "PRAGMA locking_mode = exclusive"
>
> I am not familiar with any of these or even how to set them. Is there any chance that you could point me in the right direction to look into what these options do and how to set them?

They are documented on sqlite's web site :
	http://www.sqlite.org/pragma.html

This may help you drop something in:

EBLog::logType SavvDictionary::fastDBWriteMode( QSqlDatabase db )
{
     QString query;

     EBLog::log( EBLog::info, tr( "Set fast write mode." ) );
     query = "PRAGMA synchronous";
     if ( queryDBWriteMode( db ) != EBLog::success )
         return EBLog::error;
     query = "PRAGMA synchronous = off";
     if ( pragmaSet( query, db ) != EBLog::success )
         return EBLog::error;
     query = "PRAGMA journal_mode = off";
     if ( pragmaSet( query, db ) != EBLog::success )
         return EBLog::error;
     query = "PRAGMA locking_mode = exclusive";
     if ( pragmaSet( query, db ) != EBLog::success )
         return EBLog::error;
     if ( queryDBWriteMode( db ) != EBLog::success )
         return EBLog::error;
     return EBLog::success;
}

EBLog::logType SavvDictionary::normalDBWriteMode( QSqlDatabase db )
{
     QString query;

     EBLog::log( EBLog::info, tr( "Restore normal write mode." ) );
     if ( queryDBWriteMode( db ) != EBLog::success )
         return EBLog::error;
     query = "PRAGMA synchronous = full";
     if ( pragmaSet( query, db ) != EBLog::success )
         return EBLog::error;
     query = "PRAGMA journal_mode = delete";
     if ( pragmaSet( query, db ) != EBLog::success )
         return EBLog::error;
     query = "PRAGMA locking_mode = normal";
     if ( pragmaSet( query, db ) != EBLog::success )
         return EBLog::error;
     if ( queryDBWriteMode( db ) != EBLog::success )
         return EBLog::error;
     return EBLog::success;
}

EBLog::logType SavvDictionary::queryDBWriteMode( QSqlDatabase db )
{
     QString query;

     query = "PRAGMA synchronous";
     if ( pragmaGet( query, db ) != EBLog::success )
         return EBLog::error;
     query = "PRAGMA journal_mode";
     if ( pragmaGet( query, db ) != EBLog::success )
         return EBLog::error;
     query = "PRAGMA locking_mode";
     if ( pragmaGet( query, db ) != EBLog::success )
         return EBLog::error;
     return EBLog::success;
}

EBLog::logType SavvDictionary::pragmaSet( const QString & query, const 
QSqlDatabase & db )
{
     QSqlQuery pragmaQuery( db );

     if ( !pragmaQuery.exec( query ) ) {
         close();
         return EBLog::log( EBLog::error, pragmaQuery.lastError().text() 
+ ", " + query );
     }
     EBLog::log( EBLog::info, query, EBLog::noshow );
     return EBLog::success;
}

EBLog::logType SavvDictionary::pragmaGet( const QString & query, const 
QSqlDatabase & db )
{
     QSqlQuery pragmaQuery( db );

     if ( !pragmaQuery.exec( query ) ) {
         close();
         return EBLog::log( EBLog::error, pragmaQuery.lastError().text() 
+ ", " + query );
     }
     if ( !pragmaQuery.next() ) {
         return EBLog::log( EBLog::error, pragmaQuery.lastError().text() 
+ ", " + query );
         close();
     }
     EBLog::log( EBLog::info, query + ", value = " + pragmaQuery.value( 
0 ).toString(), EBLog::noshow );
     return EBLog::success;
}

You'll have to hack out the EBLog stuff unless you'd like me to send it.

Regards
-- 
Alex