oracle provider: enable server-side simplification only with Locator >=11g or Spatial

Author: jef-n

src/core/qgsvectordataprovider.cpp

@@ -216,7 +216,7 @@ QString QgsVectorDataProvider::capabilitiesString() const
 
   if ( abilities & QgsVectorDataProvider::ChangeFeatures )
   {
-    abilitiesList += tr( "Change Geometries and Attributes at once" );
+    abilitiesList += tr( "Joint Geometry and Attributes updates" );
     QgsDebugMsg( "Capability: change attributes and geometries at once" );
   }
 

src/providers/oracle/qgsoracleconn.cpp

@@ -59,6 +59,7 @@ QgsOracleConn::QgsOracleConn( QgsDataSourceURI uri )
     : mRef( 1 )
     , mCurrentUser( QString::null )
     , mHasSpatial( -1 )
+    , mMajorVersion( -1 )
 {
   QgsDebugMsg( QString( "New Oracle connection for " ) + uri.connectionInfo() );
 
@@ -773,6 +774,21 @@ QString QgsOracleConn::databaseName( QString database, QString host, QString por
   return db;
 }
 
+int QgsOracleConn::majorVersion()
+{
+  if ( mMajorVersion == -1 )
+  {
+    QSqlQuery qry( mDatabase );
+    if ( exec( qry, "SELECT banner FROM v$version WHERE banner LIKE 'Oracle Database%'" ) && qry.next() )
+    {
+      QRegExp vers( "([0-9]+)\\.[0-9\\.]+[0-9]" );
+      if ( vers.indexIn( qry.value( 0 ).toString() ) >= 0 )
+        mMajorVersion = vers.cap( 1 ).toInt();
+    }
+  }
+  return mMajorVersion;
+}
+
 bool QgsOracleConn::hasSpatial()
 {
   if ( mHasSpatial == -1 )

src/providers/oracle/qgsoracleconn.h

@@ -139,6 +139,7 @@ class QgsOracleConn : public QObject
     QString currentUser();
 
     bool hasSpatial();
+    int majorVersion();
 
     static const int sGeomTypeSelectLimit;
 
@@ -177,6 +178,9 @@ class QgsOracleConn : public QObject
     //! has spatial
     int mHasSpatial;
 
+    //! major database version
+    int mMajorVersion;
+
     QSqlDatabase mDatabase;
     QSqlQuery mQuery;
 

src/providers/oracle/qgsoraclefeatureiterator.cpp

@@ -413,7 +413,7 @@ bool QgsOracleFeatureIterator::openQuery( QString whereClause )
 
 bool QgsOracleFeatureIterator::providerCanSimplify( QgsSimplifyMethod::MethodType methodType ) const
 {
-  return methodType == QgsSimplifyMethod::OptimizeForRendering;
+  return ( mConnection->majorVersion() > 10 || mConnection->hasSpatial() ) && methodType == QgsSimplifyMethod::OptimizeForRendering;
 }
 
 // -----------

src/providers/oracle/qgsoracleprovider.cpp

@@ -747,8 +747,12 @@ bool QgsOracleProvider::hasSufficientPermsAndCapabilities()
 
   mEnabledCapabilities = QgsVectorDataProvider::SelectAtId | QgsVectorDataProvider::SelectGeometryAtId;
 
-  // supports geometry simplification on provider side
-  mEnabledCapabilities |= QgsVectorDataProvider::SimplifyGeometries;
+  if ( mConnection->majorVersion() > 10 || mConnection->hasSpatial() )
+  {
+    // 10g doesn't support SDO_UTIL in Oracle Locator
+    // supports geometry simplification on provider side
+    mEnabledCapabilities |= QgsVectorDataProvider::SimplifyGeometries;
+  }
 
   QSqlQuery qry( *mConnection );
   if ( !mIsQuery )