maria-developers team mailing list archive

[Sergey Petrunia <psergey@xxxxxxxxxxxx>]

#At lp:maria based on revid:psergey@xxxxxxxxxxxx-20090614100110-u7l54gk0b6zbtj50

 2713 Sergey Petrunia	2009-06-14
      MWL#17: Table elimination
      - Fix the previous cset: take into account that select_lex may be printed when 
       1. There is no select_lex->join at all (in that case, assume that no tables were eliminated)
       2. select_lex->join exists but there was no JOIN::optimize() call yet. handle this by initializing join->eliminated really early. 
      modified:
        sql/sql_select.cc
        sql/sql_select.h

per-file messages:
  sql/sql_select.cc
    MWL#17: Table elimination
    - Fix the previous cset: take into account that select_lex may be printed when 
     1. There is no select_lex->join at all (in that case, assume that no tables were eliminated)
     2. select_lex->join exists but there was no JOIN::optimize() call yet. handle this by initializing join->eliminated really early.
  sql/sql_select.h
    MWL#17: Table elimination
    - Fix the previous cset: take into account that select_lex may be printed when 
     1. There is no select_lex->join at all (in that case, assume that no tables were eliminated)
     2. select_lex->join exists but there was no JOIN::optimize() call yet. handle this by initializing join->eliminated really early.
=== modified file 'sql/sql_select.cc'
--- a/sql/sql_select.cc	2009-06-14 10:01:10 +0000
+++ b/sql/sql_select.cc	2009-06-14 12:35:04 +0000
@@ -2731,7 +2731,7 @@ static void eliminate_tables(JOIN *join,
   table_map used_tables;
   DBUG_ENTER("eliminate_tables");
   
-  join->eliminated_tables= 0;
+  DBUG_ASSERT(join->eliminated_tables == 0);
   
   /* MWL#17 is only about outer join elimination, so: */
   if (!join->outer_join)
@@ -16888,7 +16888,7 @@ bool mysql_explain_union(THD *thd, SELEC
     unit->fake_select_lex->options|= SELECT_DESCRIBE;
     if (!(res= unit->prepare(thd, result, SELECT_NO_UNLOCK | SELECT_DESCRIBE)))
       res= unit->exec();
-    res|= unit->cleanup();
+    //psergey-move: res|= unit->cleanup();
   }
   else
   {
@@ -17164,7 +17164,7 @@ void st_select_lex::print(THD *thd, Stri
   {
     str->append(STRING_WITH_LEN(" from "));
     /* go through join tree */
-    print_join(thd, join->eliminated_tables, str, &top_join_list, query_type);
+    print_join(thd, join? join->eliminated_tables: 0, str, &top_join_list, query_type);
   }
   else if (where)
   {

=== modified file 'sql/sql_select.h'
--- a/sql/sql_select.h	2009-06-14 10:01:10 +0000
+++ b/sql/sql_select.h	2009-06-14 12:35:04 +0000
@@ -427,6 +427,7 @@ public:
     table= 0;
     tables= 0;
     const_tables= 0;
+    eliminated_tables= 0;
     join_list= 0;
     sort_and_group= 0;
     first_record= 0;