MWL#90: Subqueries: Inside-out execution for non-semijoin materialized...

MWL#90: Subqueries: Inside-out execution for non-semijoin materialized subqueries that are AND-parts of the WHERE
- Remove JOIN::all_tables as it is not useful.
- Better wording in comments

sql/opt_subselect.cc

@@ -2655,9 +2655,11 @@ bool setup_sj_materialization(JOIN_TAB *tab)
          then substitute_for_best_equal_field() will change the conditions
          according to the join order:
 
-           it1
-           it2    it1.col=it2.col
-           ot     cond(it1.col)
+         table | attached condition
+         ------+--------------------
+          it1  |
+          it2  | it1.col=it2.col
+          ot   | cond(it1.col)
 
          although we've originally had "SELECT it2.col", conditions attached 
          to subsequent outer tables will refer to it1.col, so SJM-Scan will

sql/sql_select.cc

@@ -2971,7 +2971,7 @@ make_join_statistics(JOIN *join, TABLE_LIST *tables_arg, COND *conds,
 
   join->join_tab=stat;
   join->map2table=stat_ref;
-  join->table= join->all_tables=table_vector;
+  join->table= table_vector;
   join->const_tables=const_count;
   join->found_const_table_map=found_const_table_map;
 
@@ -4132,7 +4132,7 @@ static void optimize_keyuse(JOIN *join, DYNAMIC_ARRAY *keyuse_array)
       for (tablenr=0 ; ! (map & 1) ; map>>=1, tablenr++) ;
       if (map == 1)			// Only one table
       {
-	TABLE *tmp_table=join->all_tables[tablenr];
+	TABLE *tmp_table=join->table[tablenr];
 	keyuse->ref_table_rows= max(tmp_table->file->stats.records, 100);
       }
     }

sql/sql_select.h

@@ -1373,8 +1373,11 @@ class JOIN :public Sql_alloc
   JOIN_TAB *join_tab,**best_ref;
   JOIN_TAB **map2table;    ///< mapping between table indexes and JOIN_TABs
   JOIN_TAB *join_tab_save; ///< saved join_tab for subquery reexecution
+  /*
+    Base tables participating in the join. After join optimization is done, the
+    tables are stored in the join order.
+  */
   TABLE    **table;
-  TABLE    **all_tables;
   /**
     The table which has an index that allows to produce the requried ordering.
     A special value of 0x1 means that the ordering will be produced by