diff options
Diffstat (limited to 'sql/sql_explain.cc')
| -rw-r--r-- | sql/sql_explain.cc | 15 |
1 files changed, 13 insertions, 2 deletions
diff --git a/sql/sql_explain.cc b/sql/sql_explain.cc index 7c3918bfd20..8dba457b918 100644 --- a/sql/sql_explain.cc +++ b/sql/sql_explain.cc @@ -714,7 +714,11 @@ int Explain_node::print_explain_for_children(Explain_query *query, for (int i= 0; i < (int) children.elements(); i++) { Explain_node *node= query->get_node(children.at(i)); - if (node->print_explain(query, output, explain_flags, is_analyze)) + /* + Note: node may not be present because for certain kinds of subqueries, + the optimizer is not able to see that they were eliminated. + */ + if (node && node->print_explain(query, output, explain_flags, is_analyze)) return 1; } return 0; @@ -759,8 +763,15 @@ void Explain_node::print_explain_json_for_children(Explain_query *query, for (int i= 0; i < (int) children.elements(); i++) { Explain_node *node= query->get_node(children.at(i)); - /* Derived tables are printed inside Explain_table_access objects */ + /* + Note: node may not be present because for certain kinds of subqueries, + the optimizer is not able to see that they were eliminated. + */ + if (!node) + continue; + + /* Derived tables are printed inside Explain_table_access objects */ if (!is_connection_printable_in_json(node->connection_type)) continue; |