diff --git a/core/DataTable.php b/core/DataTable.php
index e985f09b7591dee385acefd8d0345168af061386..211b1837f53ae3154578f3d0848e3b67ddb1b719 100644
--- a/core/DataTable.php
+++ b/core/DataTable.php
@@ -485,7 +485,7 @@ class DataTable implements DataTableInterface
                     $this->addRow($row);
                 }
             } else {
-                $rowFound->sumRow($row, $copyMeta = true, $this->columnAggregationOperations);
+                $rowFound->sumRow($row, $copyMeta = true, $this->getMetadata(self::COLUMN_AGGREGATION_OPS_METADATA_NAME));
 
                 // if the row to add has a subtable whereas the current row doesn't
                 // we simply add it (cloning the subtable)
@@ -494,7 +494,7 @@ class DataTable implements DataTableInterface
                 if (($idSubTable = $row->getIdSubDataTable()) !== null) {
                     $subTable = Manager::getInstance()->getTable($idSubTable);
                     $subTable->metadata[self::COLUMN_AGGREGATION_OPS_METADATA_NAME]
-                        = $this->metadata[self::COLUMN_AGGREGATION_OPS_METADATA_NAME];
+                        = $this->getMetadata(self::COLUMN_AGGREGATION_OPS_METADATA_NAME);
                     $rowFound->sumSubtable($subTable);
                 }
             }
@@ -644,7 +644,8 @@ class DataTable implements DataTableInterface
                 $columns = array('label' => self::LABEL_SUMMARY_ROW) + $row->getColumns();
                 $this->addSummaryRow(new Row(array(Row::COLUMNS => $columns)));
             } else {
-                $this->summaryRow->sumRow($row, $enableCopyMetadata = false, $this->columnAggregationOperations);
+                $this->summaryRow->sumRow(
+                    $row, $enableCopyMetadata = false, $this->getMetadata(self::COLUMN_AGGREGATION_OPS_METADATA_NAME));
             }
             return $this->summaryRow;
         }
@@ -762,7 +763,7 @@ class DataTable implements DataTableInterface
         foreach ($this->getRows() as $row) {
             $columns = $row->getColumns();
             foreach ($columns as $column => $value) {
-                if (strpos($column, $name) === 0) {
+                if (strpos($column, $namePrefix) === 0) {
                     $columnValues[] = $row->getColumn($column);
                 }
             }
@@ -1437,7 +1438,7 @@ class DataTable implements DataTableInterface
                     $table = new DataTable();
                     $table->setMaximumAllowedRows($maxSubtableRows);
                     $table->metadata[self::COLUMN_AGGREGATION_OPS_METADATA_NAME]
-                        = $this->metadata[self::COLUMN_AGGREGATION_OPS_METADATA_NAME];
+                        = $this->getMetadata(self::COLUMN_AGGREGATION_OPS_METADATA_NAME);
                     $next->setSubtable($table);
                     // Summary row, has no metadata
                     $next->deleteMetadata();
@@ -1480,7 +1481,7 @@ class DataTable implements DataTableInterface
                         if ($existing === false) {
                             $result->addSummaryRow($copy);
                         } else {
-                            $existing->sumRow($copy, $copyMeta = true, $this->columnAggregationOperations);
+                            $existing->sumRow($copy, $copyMeta = true, $this->getMetadata(self::COLUMN_AGGREGATION_OPS_METADATA_NAME));
                         }
                     } else {
                         if ($labelColumn !== false) {
diff --git a/core/DataTable/Filter/AddSummaryRow.php b/core/DataTable/Filter/AddSummaryRow.php
index 0a838d5b13177b00041231cad768c3dbaa294fe5..371b6df1fe343dc76be91e663ce4ff19f6c72b5f 100644
--- a/core/DataTable/Filter/AddSummaryRow.php
+++ b/core/DataTable/Filter/AddSummaryRow.php
@@ -78,10 +78,10 @@ class AddSummaryRow extends Filter
 
                 //FIXME: I'm not sure why it could return false, but it was reported in: http://forum.piwik.org/read.php?2,89324,page=1#msg-89442
                 if ($summaryRow) {
-                    $newRow->sumRow($summaryRow, $enableCopyMetadata = false, $table->metadata[DataTable::COLUMN_AGGREGATION_OPS_METADATA_NAME]);
+                    $newRow->sumRow($summaryRow, $enableCopyMetadata = false, $table->getMetadata(DataTable::COLUMN_AGGREGATION_OPS_METADATA_NAME));
                 }
             } else {
-                $newRow->sumRow($rows[$i], $enableCopyMetadata = false, $table->metadata[DataTable::COLUMN_AGGREGATION_OPS_METADATA_NAME]);
+                $newRow->sumRow($rows[$i], $enableCopyMetadata = false, $table->getMetadata(DataTable::COLUMN_AGGREGATION_OPS_METADATA_NAME));
             }
         }
 
diff --git a/core/DataTable/Filter/GroupBy.php b/core/DataTable/Filter/GroupBy.php
index 0ee3fa6e6c4885cf7b3417d087c7281bfaba25d0..e6305a43cdc0fb46185ad133e3ab501c3b022c9f 100755
--- a/core/DataTable/Filter/GroupBy.php
+++ b/core/DataTable/Filter/GroupBy.php
@@ -87,7 +87,7 @@ class GroupBy extends Filter
             } else {
                 // if we have already encountered this group by value, we add this row to the
                 // row that will be kept, and mark this one for deletion
-                $groupByRows[$groupByValue]->sumRow($row, $copyMeta = true, $table->metadata[DataTable::COLUMN_AGGREGATION_OPS_METADATA_NAME]);
+                $groupByRows[$groupByValue]->sumRow($row, $copyMeta = true, $table->getMetadata(DataTable::COLUMN_AGGREGATION_OPS_METADATA_NAME));
                 $nonGroupByRowIds[] = $rowId;
             }
         }
diff --git a/core/DataTable/Row.php b/core/DataTable/Row.php
index 36f057586f92f1fd05c3a417d6d042a00fa18505..ae9e238ee30a4574f1e57e52a30af5ac956d570f 100644
--- a/core/DataTable/Row.php
+++ b/core/DataTable/Row.php
@@ -288,7 +288,7 @@ class Row
             $this->addSubtable($thisSubTable);
         }
         $thisSubTable->metadata[DataTable::COLUMN_AGGREGATION_OPS_METADATA_NAME]
-            = $subTable->metadata[DataTable::COLUMN_AGGREGATION_OPS_METADATA_NAME];
+            = $subTable->getMetadata(DataTable::COLUMN_AGGREGATION_OPS_METADATA_NAME);
         $thisSubTable->addDataTable($subTable);
     }
 
diff --git a/core/DataTable/Row/DataTableSummaryRow.php b/core/DataTable/Row/DataTableSummaryRow.php
index 86032814563feba9cc5005e53f4aba6a189e69d5..9b47b67df95e75fd4cf10fc69c793db1a3ab7a7d 100644
--- a/core/DataTable/Row/DataTableSummaryRow.php
+++ b/core/DataTable/Row/DataTableSummaryRow.php
@@ -59,7 +59,7 @@ class DataTableSummaryRow extends Row
     private function sumTable($table)
     {
         foreach ($table->getRows() as $row) {
-            $this->sumRow($row, $enableCopyMetadata = false, $table->metadata[DataTable::COLUMN_AGGREGATION_OPS_METADATA_NAME]);
+            $this->sumRow($row, $enableCopyMetadata = false, $table->getMetadata(DataTable::COLUMN_AGGREGATION_OPS_METADATA_NAME));
         }
     }
 }
diff --git a/tests/PHPUnit/BaseFixture.php b/tests/PHPUnit/BaseFixture.php
index 1d9c8b731f9138e1c91dd33741057f80991384c0..3ab347fd31d77c3e329f22ee4c3cc15ad8baf118 100644
--- a/tests/PHPUnit/BaseFixture.php
+++ b/tests/PHPUnit/BaseFixture.php
@@ -383,7 +383,6 @@ abstract class Test_Piwik_BaseFixture extends PHPUnit_Framework_Assert
 
         // run the command
         exec($cmd, $output, $result);
-        echo "OUTPUT: ".implode("\n", $output);
         if ($result !== 0) {
             throw new Exception("log importer failed: " . implode("\n", $output) . "\n\ncommand used: $cmd");
         }