Limit results to what was asked for

src/libtomahawk/database/databasecommand_genericselect.cpp

@@ -27,10 +27,11 @@
 using namespace Tomahawk;
 
 
-DatabaseCommand_GenericSelect::DatabaseCommand_GenericSelect( const QString& sqlSelect, QueryType type, QObject* parent )
+DatabaseCommand_GenericSelect::DatabaseCommand_GenericSelect( const QString& sqlSelect, QueryType type, int limit, QObject* parent )
     : DatabaseCommand( parent )
     , m_sqlSelect( sqlSelect )
     , m_queryType( type )
+    , m_limit( limit )
 {
 }
 
@@ -40,7 +41,7 @@ DatabaseCommand_GenericSelect::exec( DatabaseImpl* dbi )
 {
     TomahawkSqlQuery query = dbi->newquery();
 
-    query.prepare( m_sqlSelect );
+    query.prepare( QString( "%1 %2;" ).arg( m_sqlSelect ).arg( m_limit > -1 ? QString( " LIMIT %1" ).arg( m_limit ) : QString() ) );
     query.exec();
 
     QList< query_ptr > queries;

src/libtomahawk/database/databasecommand_genericselect.h

@@ -44,6 +44,10 @@
  *
  * Any extra values in the resultset will be returned as a QVariantList attached to the "data" property of each query_ptr
  *
+ * Notes:
+ *      * Do not trail your SQL command with ;
+ *      * Do not use the LIMIT command if you pass limitResults > -1
+ *
  */
 class DLLEXPORT DatabaseCommand_GenericSelect : public DatabaseCommand
 {
@@ -56,7 +60,7 @@ public:
         Album
     };
 
-    explicit DatabaseCommand_GenericSelect( const QString& sqlSelect, QueryType type, QObject* parent = 0 );
+    explicit DatabaseCommand_GenericSelect( const QString& sqlSelect, QueryType type, int limitResults = -1, QObject* parent = 0 );
     virtual void exec( DatabaseImpl* lib );
     virtual bool doesMutates() const { return false; }
 
@@ -70,6 +74,7 @@ signals:
 private:
     QString m_sqlSelect;
     QueryType m_queryType;
+    int m_limit;
 };
 
 #endif // DATABASECOMMAND_GENERICSELECT_H

src/libtomahawk/playlist/dynamic/database/DatabaseGenerator.cpp

@@ -55,7 +55,6 @@ DatabaseFactory::typeSelectors() const
 
 DatabaseGenerator::DatabaseGenerator ( QObject* parent )
     : GeneratorInterface ( parent )
-    , m_curCountRequested( 0 )
 {
     // defaults
     m_type = "database";
@@ -125,8 +124,9 @@ DatabaseGenerator::generate( int number )
 
         tDebug() << "Generated sql query:" << control.dynamicCast< DatabaseControl >()->sql();
         DatabaseCommand_GenericSelect* cmd = new DatabaseCommand_GenericSelect( control.dynamicCast< DatabaseControl >()->sql(),
-                                                                                static_cast< DatabaseCommand_GenericSelect::QueryType >( control->match().toInt() ) );
-        m_curCountRequested = number; // Can't set count on dbcmd itself as sender() in slot is 0
+                                                                                static_cast< DatabaseCommand_GenericSelect::QueryType >( control->match().toInt() ),
+                                                                                number
+                                                                              );
 
         connect( cmd, SIGNAL( tracks( QList<Tomahawk::query_ptr> ) ), this, SLOT( tracksGenerated( QList<Tomahawk::query_ptr> ) ) );
         Database::instance()->enqueue( QSharedPointer< DatabaseCommand >( cmd ) );
@@ -139,15 +139,7 @@ DatabaseGenerator::generate( int number )
 void
 DatabaseGenerator::tracksGenerated ( const QList< query_ptr >& tracks )
 {
-    if( m_curCountRequested == 0 )
-        return;
-
-    if ( m_curCountRequested < tracks.size() )
-        emit generated( tracks.mid( 0, m_curCountRequested ) );
-    else
-        emit generated( tracks );
-
-    m_curCountRequested = 0;
+    emit generated( tracks );
 }
 
 

src/libtomahawk/playlist/dynamic/database/DatabaseGenerator.h

@@ -73,7 +73,6 @@ namespace Tomahawk
 
     private:
         QPixmap m_logo;
-        int m_curCountRequested;
     };
 
 };

src/libtomahawk/widgets/SocialPlaylistWidget.cpp

@@ -118,7 +118,7 @@ SocialPlaylistWidget::playlist1Created()
 {
     Q_ASSERT( m_coolQuery1->generator().dynamicCast< DatabaseGenerator >() );
 
-    QString sql = "select track.name, artist.name, count(*) as counter from (select track from playback_log group by track, source), track, artist where track.id = track and artist.id = track.artist group by track order by counter desc limit 0,100;";
+    QString sql = "select track.name, artist.name, count(*) as counter from (select track from playback_log group by track, source), track, artist where track.id = track and artist.id = track.artist group by track order by counter desc";
 
     dyncontrol_ptr control = m_coolQuery1->generator().dynamicCast< DatabaseGenerator >()->createControl( sql, DatabaseCommand_GenericSelect::Track, "This is a cool playlist!" );
     m_coolQuery1->createNewRevision( uuid() );