MDEV-4840: Wrong result (missing rows) on LEFT JOIN with InnoDB tables

Fix two problems in table elimination code:
- Before marking a "value" as bound, check if it is already bound. Marking the 
  same value as bound twice could confuse a module that depends on this value, 
  because Dep_module_XXX use counters to know when they become bound.

- When checking whether field is part of a key, ignore "extended keys" property.

1 files changed, 6 insertions, 3 deletions

diff --git a/sql/opt_table_elimination.cc b/sql/opt_table_elimination.cc
index 33164c1ed12..4a10d402fac 100644
--- a/sql/opt_table_elimination.cc
+++ b/sql/opt_table_elimination.cc
@@ -892,8 +892,11 @@ bool Dep_analysis_context::run_wave(List<Dep_module> *new_bound_modules)
       iter= module->init_unbound_values_iter(iter_buf);
       while ((value= module->get_next_unbound_value(this, iter)))
       {
-        value->make_bound();
-        new_bound_values.push_back(value);
+        if (!value->is_bound())
+        {
+          value->make_bound();
+          new_bound_values.push_back(value);
+        }
       }
     }
     new_bound_modules->empty();
@@ -1740,7 +1743,7 @@ Dep_module* Dep_value_field::get_next_unbound_module(Dep_analysis_context *dac,
     - have this field as a part of them
   */
   while (key_dep && (key_dep->is_applicable() ||
-         !field->part_of_key.is_set(key_dep->keyno)))
+         !field->part_of_key_not_clustered.is_set(key_dep->keyno)))
   {
     key_dep= key_dep->next_table_key;
   }