From 57ea79f605aad10c3226b26d63b2010bca34c718 Mon Sep 17 00:00:00 2001
From: Martin Dobias <wonder.sk@gmail.com>
Date: Thu, 17 Nov 2011 01:07:10 -0300
Subject: [PATCH] Optimize SpatiaLite feature reading speed

---
 src/providers/spatialite/qgsspatialiteprovider.cpp | 6 ++++--
 src/providers/spatialite/qgsspatialiteprovider.h   | 3 +++
 2 files changed, 7 insertions(+), 2 deletions(-)

diff --git a/src/providers/spatialite/qgsspatialiteprovider.cpp b/src/providers/spatialite/qgsspatialiteprovider.cpp
index c13bf33a4990..9791eddbd6f4 100644
--- a/src/providers/spatialite/qgsspatialiteprovider.cpp
+++ b/src/providers/spatialite/qgsspatialiteprovider.cpp
@@ -795,8 +795,7 @@ bool QgsSpatiaLiteProvider::getFeature( sqlite3_stmt *stmt, bool fetchGeometry,
         }
         if ( fetchGeometry )
         {
-          QString geoCol = QString( "AsBinary(%1)" ).arg( quotedIdentifier( mGeometryColumn ) );
-          if ( strcasecmp( geoCol.toUtf8().constData(), sqlite3_column_name( stmt, ic ) ) == 0 )
+          if ( ic == mGeomColIdx )
           {
             if ( sqlite3_column_type( stmt, ic ) == SQLITE_BLOB )
             {
@@ -3247,6 +3246,7 @@ bool QgsSpatiaLiteProvider::prepareStatement(
   QString primaryKey = !isQuery ? "ROWID" : quotedIdentifier( mPrimaryKey );
 
   QString sql = QString( "SELECT %1" ).arg( primaryKey );
+  int colIdx = 1; // column 0 is primary key
   for ( QgsAttributeList::const_iterator it = fetchAttributes.constBegin(); it != fetchAttributes.constEnd(); ++it )
   {
     const QgsField & fld = field( *it );
@@ -3258,10 +3258,12 @@ bool QgsSpatiaLiteProvider::prepareStatement(
       fieldname = QString( "AsText(%1)" ).arg( fieldname );
     }
     sql += "," + fieldname;
+    colIdx++;
   }
   if ( fetchGeometry )
   {
     sql += QString( ", AsBinary(%1)" ).arg( quotedIdentifier( mGeometryColumn ) );
+    mGeomColIdx = colIdx;
   }
   sql += QString( " FROM %1" ).arg( mQuery );
 
diff --git a/src/providers/spatialite/qgsspatialiteprovider.h b/src/providers/spatialite/qgsspatialiteprovider.h
index 5547219e1670..b184c40a3b40 100644
--- a/src/providers/spatialite/qgsspatialiteprovider.h
+++ b/src/providers/spatialite/qgsspatialiteprovider.h
@@ -382,6 +382,9 @@ class QgsSpatiaLiteProvider: public QgsVectorDataProvider
 
     const QgsField & field( int index ) const;
 
+    /** geometry column index used when fetching geometry */
+    int mGeomColIdx;
+
     /**
     * internal utility functions used to handle common SQLite tasks
     */