MDEV-8289: Semijoin inflates number of rows in query result

- Make semi-join optimizer not to choose LooseScan
  when 1) the index is not covered and 2) full index
  scan will be required.

- Make sure that the code in make_join_select() that may change
  full index scan into a range scan is not invoked when the table
  uses full scan.

1 files changed, 1 insertions, 2 deletions

diff --git a/sql/sql_select.h b/sql/sql_select.h
index 61157130f50..bbeb2aa6952 100644
--- a/sql/sql_select.h
+++ b/sql/sql_select.h
@@ -717,8 +717,7 @@ public:
                                struct st_position *pos,
                                struct st_position *loose_scan_pos);
   friend bool get_best_combination(JOIN *join);
-  friend int setup_semijoin_dups_elimination(JOIN *join, ulonglong options,
-                                             uint no_jbuf_after);
+  friend int setup_semijoin_loosescan(JOIN *join);
   friend void fix_semijoin_strategies_for_picked_join_order(JOIN *join);
 };