add execute sql with iterator

qgis · Jan 29, 2021 · d0491b6 · d0491b6
1 parent 1d7bfe2
commit d0491b6
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Showing 3 changed files with 74 additions and 22 deletions.
diff --git a/src/providers/oracle/qgsoracleproviderconnection.cpp b/src/providers/oracle/qgsoracleproviderconnection.cpp
@@ -22,6 +22,7 @@
 #include "qgsapplication.h"
 
 #include <QSqlRecord>
+#include <QSqlField>
 
 const QStringList CONFIGURATION_PARAMETERS
 {
@@ -152,15 +153,11 @@ QList<QgsVectorDataProvider::NativeType> QgsOracleProviderConnection::nativeType
   return types;
 }
 
-QList<QVariantList> QgsOracleProviderConnection::executeSqlPrivate( const QString &sql, QgsFeedback *feedback ) const
+QgsAbstractDatabaseProviderConnection::QueryResult QgsOracleProviderConnection::executeSqlPrivate( const QString &sql, QgsFeedback *feedback ) const
 {
-  QList<QVariantList> results;
-
   // Check feedback first!
   if ( feedback && feedback->isCanceled() )
-  {
-    return results;
-  }
+    return QgsAbstractDatabaseProviderConnection::QueryResult();
 
   QgsPoolOracleConn pconn( QgsDataSourceUri{ uri() }.connectionInfo( false ) );
   if ( !pconn.get() )
@@ -169,9 +166,7 @@ QList<QVariantList> QgsOracleProviderConnection::executeSqlPrivate( const QStrin
   }
 
   if ( feedback && feedback->isCanceled() )
-  {
-    return results;
-  }
+    return QgsAbstractDatabaseProviderConnection::QueryResult();
 
   QSqlQuery qry( *pconn.get() );
   if ( !qry.exec( sql ) )
@@ -181,22 +176,50 @@ QList<QVariantList> QgsOracleProviderConnection::executeSqlPrivate( const QStrin
                                               qry.lastError().text() ) );
   }
 
-  const int nbFields = qry.record().count();
-  while ( qry.next() )
+  if ( feedback && feedback->isCanceled() )
+    return QgsAbstractDatabaseProviderConnection::QueryResult();
+
+  if ( qry.isActive() )
   {
-    if ( feedback && feedback->isCanceled() )
+    const QSqlRecord rec { qry.record() };
+    const int numCols { rec.count() };
+    auto iterator = std::make_shared<QgsOracleProviderResultIterator>( numCols, qry );
+    QgsAbstractDatabaseProviderConnection::QueryResult results( iterator );
+    results.setRowCount( qry.size() );
+    for ( int idx = 0; idx < numCols; ++idx )
     {
-      return results;
+      results.appendColumn( rec.field( idx ).name() );
     }
+    iterator->nextRow();
+    return results;
+  }
 
-    QVariantList cols;
-    for ( int i = 0; i < nbFields; i++ )
-      cols << qry.value( i );
+  return QgsAbstractDatabaseProviderConnection::QueryResult();
+}
 
-    results << cols;
-  }
+QVariantList QgsOracleProviderResultIterator::nextRow()
+{
+  const QVariantList currentRow( mNextRow );
+  mNextRow = nextRowPrivate();
+  return currentRow;
+}
 
-  return results;
+bool QgsOracleProviderResultIterator::hasNextRow() const
+{
+  return ! mNextRow.isEmpty();
+}
+
+QVariantList QgsOracleProviderResultIterator::nextRowPrivate()
+{
+  QVariantList row;
+  if ( mQuery.next() )
+  {
+    for ( int col = 0; col < mColumnCount; ++col )
+    {
+      row.push_back( mQuery.value( col ) );
+    }
+  }
+  return row;
 }
 
 void QgsOracleProviderConnection::createVectorTable( const QString &schema,
@@ -326,3 +349,9 @@ void QgsOracleProviderConnection::dropVectorTable( const QString &schema, const
                      .arg( QgsOracleConn::quotedIdentifier( schema ) )
                      .arg( QgsOracleConn::quotedIdentifier( name ) ) );
 }
+
+QgsAbstractDatabaseProviderConnection::QueryResult QgsOracleProviderConnection::execSql( const QString &sql, QgsFeedback *feedback ) const
+{
+  checkCapability( Capability::ExecuteSql );
+  return executeSqlPrivate( sql, feedback );
+}
diff --git a/src/providers/oracle/qgsoracleproviderconnection.h b/src/providers/oracle/qgsoracleproviderconnection.h
@@ -17,6 +17,28 @@
 #define QGSORACLEPROVIDERCONNECTION_H
 #include "qgsabstractdatabaseproviderconnection.h"
 
+#include <QSqlQuery>
+
+struct QgsOracleProviderResultIterator: public QgsAbstractDatabaseProviderConnection::QueryResult::QueryResultIterator
+{
+
+    QgsOracleProviderResultIterator( int columnCount, const QSqlQuery &query )
+      : mColumnCount( columnCount )
+      , mQuery( query )
+    {}
+
+    QVariantList nextRow() override;
+    bool hasNextRow() const override;
+
+  private:
+
+    int mColumnCount = 0;
+    QSqlQuery mQuery;
+    QVariantList mNextRow;
+
+    QVariantList nextRowPrivate();
+
+};
 
 class QgsOracleProviderConnection : public QgsAbstractDatabaseProviderConnection
 
@@ -38,6 +60,7 @@ class QgsOracleProviderConnection : public QgsAbstractDatabaseProviderConnection
     QString tableUri( const QString &schema, const QString &name ) const override;
     void dropVectorTable( const QString &schema, const QString &name ) const override;
 
+    QgsAbstractDatabaseProviderConnection::QueryResult execSql( const QString &sql, QgsFeedback *feedback = nullptr ) const override;
     QList<QgsAbstractDatabaseProviderConnection::TableProperty> tables( const QString &schema,
         const TableFlags &flags = TableFlags() ) const override;
     void store( const QString &name ) const override;
@@ -46,7 +69,7 @@ class QgsOracleProviderConnection : public QgsAbstractDatabaseProviderConnection
 
   private:
 
-    QList<QVariantList> executeSqlPrivate( const QString &sql, QgsFeedback *feedback = nullptr ) const;
+    QgsAbstractDatabaseProviderConnection::QueryResult executeSqlPrivate( const QString &sql, QgsFeedback *feedback = nullptr ) const;
     void setDefaultCapabilities();
 };
 

diff --git a/tests/src/python/test_qgsproviderconnection_base.py b/tests/src/python/test_qgsproviderconnection_base.py
@@ -141,6 +141,7 @@ def _test_operations(self, md, conn):
             self.assertFalse('myUtf8\U0001f604NewSchema' in schemas)
 
         # Table operations
+        schema = None
         if (capabilities & QgsAbstractDatabaseProviderConnection.CreateVectorTable
             and capabilities & QgsAbstractDatabaseProviderConnection.Tables
                 and capabilities & QgsAbstractDatabaseProviderConnection.DropVectorTable):
@@ -220,9 +221,8 @@ def _test_operations(self, md, conn):
             self.assertTrue(table_property.flags() & QgsAbstractDatabaseProviderConnection.Aspatial)
 
             # Check executeSql
-            has_schema = capabilities & QgsAbstractDatabaseProviderConnection.Schemas
             if capabilities & QgsAbstractDatabaseProviderConnection.ExecuteSql:
-                if has_schema:
+                if schema:
                     table = "\"%s\".\"myNewAspatialTable\"" % schema
                 else:
                     table = 'myNewAspatialTable'