Fix possible crash when sorted column does not exist anymore

MKleusberg · MKleusberg · commit 61e13aec038d · 2019-03-06T12:01:39.000+01:00
When sorting a table or a view by a column, then removing enough columns from that table, that view, or the underlying table of the view so that the column index get out of bound, and then going back to browse that table the application crashes. This commit makes sure to ignore such columns which would cause a crash. See issue #1774.
diff --git a/src/sql/Query.cpp b/src/sql/Query.cpp
@@ -66,13 +66,16 @@ std::string Query::buildQuery(bool withRowid) const
 
     // Sorting
     std::string order_by;
-    if(m_sort.size())
+    for(const auto& sorted_column : m_sort)
     {
-        order_by = "ORDER BY ";
-        for(const auto& sorted_column : m_sort)
+        if(sorted_column.column < m_column_names.size())
             order_by += sqlb::escapeIdentifier(m_column_names.at(sorted_column.column)) + " "
                     + (sorted_column.direction == sqlb::Ascending ? "ASC" : "DESC") + ",";
+    }
+    if(order_by.size())
+    {
         order_by.pop_back();
+        order_by = "ORDER BY " + order_by;
     }
 
     return "SELECT " + selector + " FROM " + m_table.toString().toStdString() + " " + where + " " + order_by;
