QgsSpatiaLiteFeatureIterator::QgsSpatiaLiteFeatureIterator( QgsSpatiaLiteFeatureSource* source, bool ownSource, const QgsFeatureRequest& request )
: QgsAbstractFeatureIteratorFromSource<QgsSpatiaLiteFeatureSource>( source, ownSource, request )
, sqliteStatement( NULL )
, mExpressionCompiled( false )
{
mHandle = QgsSpatiaLiteConnPool::instance()->acquireConnection( mSource->mSqlitePath );
mFetchGeometry = !mSource->mGeometryColumn.isNull() && !( mRequest.flags() & QgsFeatureRequest::NoGeometry );
mHasPrimaryKey = !mSource->mPrimaryKey.isEmpty();
mRowNumber = 0;
QStringList whereClauses;
bool useFallbackWhereClause = false;
QString fallbackWhereClause;
QString whereClause;
//beware - limitAtProvider needs to be set to false if the request cannot be completely handled
//by the provider (eg utilising QGIS expression filters)
bool limitAtProvider = ( mRequest.limit() >= 0 );
if ( !request.filterRect().isNull() && !mSource->mGeometryColumn.isNull() )
{
// some kind of MBR spatial filtering is required
whereClause = whereClauseRect();
if ( ! whereClause.isEmpty() )
{
whereClauses.append( whereClause );
}
}
if ( !mSource->mSubsetString.isEmpty() )
{
whereClause = "( " + mSource->mSubsetString + ')';
if ( ! whereClause.isEmpty() )
{
whereClauses.append( whereClause );
}
}
if ( request.filterType() == QgsFeatureRequest::FilterFid )
{
whereClause = whereClauseFid();
if ( ! whereClause.isEmpty() )
{
whereClauses.append( whereClause );
}
}
else if ( request.filterType() == QgsFeatureRequest::FilterFids )
{
whereClause = whereClauseFids();
if ( ! whereClause.isEmpty() )
{
whereClauses.append( whereClause );
}
}
//IMPORTANT - this MUST be the last clause added!
else if ( request.filterType() == QgsFeatureRequest::FilterExpression )
{
if ( QSettings().value( "/qgis/compileExpressions", true ).toBool() )
{
QgsSpatiaLiteExpressionCompiler compiler = QgsSpatiaLiteExpressionCompiler( source );
QgsSqlExpressionCompiler::Result result = compiler.compile( request.filterExpression() );
if ( result == QgsSqlExpressionCompiler::Complete || result == QgsSqlExpressionCompiler::Partial )
{
whereClause = compiler.result();
if ( !whereClause.isEmpty() )
{
useFallbackWhereClause = true;
fallbackWhereClause = whereClauses.join( " AND " );
whereClauses.append( whereClause );
//if only partial success when compiling expression, we need to double-check results using QGIS' expressions
mExpressionCompiled = ( result == QgsSqlExpressionCompiler::Complete );
}
}
if ( result != QgsSqlExpressionCompiler::Complete )
{
//can't apply limit at provider side as we need to check all results using QGIS expressions
limitAtProvider = false;
}
}
else
{
limitAtProvider = false;
}
}
whereClause = whereClauses.join( " AND " );
// preparing the SQL statement
bool success = prepareStatement( whereClause, limitAtProvider ? mRequest.limit() : -1 );
if ( !success && useFallbackWhereClause )
{
//try with the fallback where clause, eg for cases when using compiled expression failed to prepare
mExpressionCompiled = false;
success = prepareStatement( fallbackWhereClause, -1 );
}
if ( !success )
{
// some error occurred
sqliteStatement = NULL;
close();
}
}
QgsSpatiaLiteFeatureIterator::QgsSpatiaLiteFeatureIterator( QgsSpatiaLiteFeatureSource* source, bool ownSource, const QgsFeatureRequest& request )
: QgsAbstractFeatureIteratorFromSource<QgsSpatiaLiteFeatureSource>( source, ownSource, request )
, sqliteStatement( nullptr )
, mExpressionCompiled( false )
{
mHandle = QgsSpatiaLiteConnPool::instance()->acquireConnection( mSource->mSqlitePath );
mFetchGeometry = !mSource->mGeometryColumn.isNull() && !( mRequest.flags() & QgsFeatureRequest::NoGeometry );
mHasPrimaryKey = !mSource->mPrimaryKey.isEmpty();
mRowNumber = 0;
QStringList whereClauses;
bool useFallbackWhereClause = false;
QString fallbackWhereClause;
QString whereClause;
//beware - limitAtProvider needs to be set to false if the request cannot be completely handled
//by the provider (eg utilising QGIS expression filters)
bool limitAtProvider = ( mRequest.limit() >= 0 );
if ( !request.filterRect().isNull() && !mSource->mGeometryColumn.isNull() )
{
// some kind of MBR spatial filtering is required
whereClause = whereClauseRect();
if ( ! whereClause.isEmpty() )
{
whereClauses.append( whereClause );
}
}
if ( !mSource->mSubsetString.isEmpty() )
{
whereClause = "( " + mSource->mSubsetString + ')';
if ( ! whereClause.isEmpty() )
{
whereClauses.append( whereClause );
}
}
if ( request.filterType() == QgsFeatureRequest::FilterFid )
{
whereClause = whereClauseFid();
if ( ! whereClause.isEmpty() )
{
whereClauses.append( whereClause );
}
}
else if ( request.filterType() == QgsFeatureRequest::FilterFids )
{
whereClause = whereClauseFids();
if ( ! whereClause.isEmpty() )
{
whereClauses.append( whereClause );
}
}
//IMPORTANT - this MUST be the last clause added!
else if ( request.filterType() == QgsFeatureRequest::FilterExpression )
{
// ensure that all attributes required for expression filter are being fetched
if ( mRequest.flags() & QgsFeatureRequest::SubsetOfAttributes && request.filterType() == QgsFeatureRequest::FilterExpression )
{
QgsAttributeList attrs = request.subsetOfAttributes();
Q_FOREACH ( const QString& field, request.filterExpression()->referencedColumns() )
{
int attrIdx = mSource->mFields.fieldNameIndex( field );
if ( !attrs.contains( attrIdx ) )
attrs << attrIdx;
}
mRequest.setSubsetOfAttributes( attrs );
}
if ( QSettings().value( "/qgis/compileExpressions", true ).toBool() )
{
QgsSpatiaLiteExpressionCompiler compiler = QgsSpatiaLiteExpressionCompiler( source );
QgsSqlExpressionCompiler::Result result = compiler.compile( request.filterExpression() );
if ( result == QgsSqlExpressionCompiler::Complete || result == QgsSqlExpressionCompiler::Partial )
{
whereClause = compiler.result();
if ( !whereClause.isEmpty() )
{
useFallbackWhereClause = true;
fallbackWhereClause = whereClauses.join( " AND " );
whereClauses.append( whereClause );
//if only partial success when compiling expression, we need to double-check results using QGIS' expressions
mExpressionCompiled = ( result == QgsSqlExpressionCompiler::Complete );
}
}
if ( result != QgsSqlExpressionCompiler::Complete )
{
//can't apply limit at provider side as we need to check all results using QGIS expressions
limitAtProvider = false;
}
}
else
{
limitAtProvider = false;
}
}
QgsSpatiaLiteFeatureIterator::QgsSpatiaLiteFeatureIterator( QgsSpatiaLiteFeatureSource* source, bool ownSource, const QgsFeatureRequest& request )
: QgsAbstractFeatureIteratorFromSource<QgsSpatiaLiteFeatureSource>( source, ownSource, request )
, sqliteStatement( nullptr )
, mExpressionCompiled( false )
{
mHandle = QgsSpatiaLiteConnPool::instance()->acquireConnection( mSource->mSqlitePath );
mFetchGeometry = !mSource->mGeometryColumn.isNull() && !( mRequest.flags() & QgsFeatureRequest::NoGeometry );
mHasPrimaryKey = !mSource->mPrimaryKey.isEmpty();
mRowNumber = 0;
QStringList whereClauses;
bool useFallbackWhereClause = false;
QString fallbackWhereClause;
QString whereClause;
//beware - limitAtProvider needs to be set to false if the request cannot be completely handled
//by the provider (eg utilising QGIS expression filters)
bool limitAtProvider = ( mRequest.limit() >= 0 );
if ( !request.filterRect().isNull() && !mSource->mGeometryColumn.isNull() )
{
// some kind of MBR spatial filtering is required
whereClause = whereClauseRect();
if ( ! whereClause.isEmpty() )
{
whereClauses.append( whereClause );
}
}
if ( !mSource->mSubsetString.isEmpty() )
{
whereClause = "( " + mSource->mSubsetString + ')';
if ( ! whereClause.isEmpty() )
{
whereClauses.append( whereClause );
}
}
if ( request.filterType() == QgsFeatureRequest::FilterFid )
{
whereClause = whereClauseFid();
if ( ! whereClause.isEmpty() )
{
whereClauses.append( whereClause );
}
}
else if ( request.filterType() == QgsFeatureRequest::FilterFids )
{
whereClause = whereClauseFids();
if ( ! whereClause.isEmpty() )
{
whereClauses.append( whereClause );
}
}
//IMPORTANT - this MUST be the last clause added!
else if ( request.filterType() == QgsFeatureRequest::FilterExpression )
{
if ( QSettings().value( "/qgis/compileExpressions", true ).toBool() )
{
QgsSpatiaLiteExpressionCompiler compiler = QgsSpatiaLiteExpressionCompiler( source );
QgsSqlExpressionCompiler::Result result = compiler.compile( request.filterExpression() );
if ( result == QgsSqlExpressionCompiler::Complete || result == QgsSqlExpressionCompiler::Partial )
{
whereClause = compiler.result();
if ( !whereClause.isEmpty() )
{
useFallbackWhereClause = true;
fallbackWhereClause = whereClauses.join( " AND " );
whereClauses.append( whereClause );
//if only partial success when compiling expression, we need to double-check results using QGIS' expressions
mExpressionCompiled = ( result == QgsSqlExpressionCompiler::Complete );
}
}
if ( result != QgsSqlExpressionCompiler::Complete )
{
//can't apply limit at provider side as we need to check all results using QGIS expressions
limitAtProvider = false;
}
}
else
{
limitAtProvider = false;
}
}
whereClause = whereClauses.join( " AND " );
// Setup the order by
QStringList orderByParts;
mOrderByCompiled = true;
if ( QSettings().value( "/qgis/compileExpressions", true ).toBool() )
{
Q_FOREACH ( const QgsFeatureRequest::OrderByClause& clause, request.orderBy() )
{
QgsSpatiaLiteExpressionCompiler compiler = QgsSpatiaLiteExpressionCompiler( source );
QgsExpression expression = clause.expression();
if ( compiler.compile( &expression ) == QgsSqlExpressionCompiler::Complete )
{
QString part;
part = compiler.result();
if ( clause.nullsFirst() )
orderByParts << QString( "%1 IS NOT NULL" ).arg( part );
else
orderByParts << QString( "%1 IS NULL" ).arg( part );
part += clause.ascending() ? " COLLATE NOCASE ASC" : " COLLATE NOCASE DESC";
orderByParts << part;
}
else
{
// Bail out on first non-complete compilation.
// Most important clauses at the beginning of the list
// will still be sent and used to pre-sort so the local
// CPU can use its cycles for fine-tuning.
mOrderByCompiled = false;
break;
}
}
}
QgsSpatiaLiteFeatureIterator::QgsSpatiaLiteFeatureIterator( QgsSpatiaLiteFeatureSource* source, bool ownSource, const QgsFeatureRequest& request )
: QgsAbstractFeatureIteratorFromSource<QgsSpatiaLiteFeatureSource>( source, ownSource, request )
, sqliteStatement( NULL )
, mExpressionCompiled( false )
{
mHandle = QgsSpatiaLiteConnPool::instance()->acquireConnection( mSource->mSqlitePath );
mFetchGeometry = !mSource->mGeometryColumn.isNull() && !( mRequest.flags() & QgsFeatureRequest::NoGeometry );
mHasPrimaryKey = !mSource->mPrimaryKey.isEmpty();
mRowNumber = 0;
QStringList whereClauses;
QString whereClause;
if ( !request.filterRect().isNull() && !mSource->mGeometryColumn.isNull() )
{
// some kind of MBR spatial filtering is required
whereClause = whereClauseRect();
if ( ! whereClause.isEmpty() )
{
whereClauses.append( whereClause );
}
}
if ( request.filterType() == QgsFeatureRequest::FilterFid )
{
whereClause = whereClauseFid();
if ( ! whereClause.isEmpty() )
{
whereClauses.append( whereClause );
}
}
else if ( request.filterType() == QgsFeatureRequest::FilterFids )
{
whereClause = whereClauseFids();
if ( ! whereClause.isEmpty() )
{
whereClauses.append( whereClause );
}
}
else if ( request.filterType() == QgsFeatureRequest::FilterExpression
&& QSettings().value( "/qgis/compileExpressions", true ).toBool() )
{
QgsSpatiaLiteExpressionCompiler compiler = QgsSpatiaLiteExpressionCompiler( source );
QgsSqlExpressionCompiler::Result result = compiler.compile( request.filterExpression() );
if ( result == QgsSqlExpressionCompiler::Complete || result == QgsSqlExpressionCompiler::Partial )
{
whereClause = compiler.result();
if ( !whereClause.isEmpty() )
{
whereClauses.append( whereClause );
//if only partial success when compiling expression, we need to double-check results using QGIS' expressions
mExpressionCompiled = ( result == QgsSqlExpressionCompiler::Complete );
}
}
}
if ( !mSource->mSubsetString.isEmpty() )
{
whereClause = "( " + mSource->mSubsetString + ')';
if ( ! whereClause.isEmpty() )
{
whereClauses.append( whereClause );
}
}
whereClause = whereClauses.join( " AND " );
// preparing the SQL statement
if ( !prepareStatement( whereClause ) )
{
// some error occurred
sqliteStatement = NULL;
close();
return;
}
}
