diff options
Diffstat (limited to 'sql/sql_select.cc')
| -rw-r--r-- | sql/sql_select.cc | 8 |
1 files changed, 8 insertions, 0 deletions
diff --git a/sql/sql_select.cc b/sql/sql_select.cc index fe239dbf949..ee23804e222 100644 --- a/sql/sql_select.cc +++ b/sql/sql_select.cc @@ -8101,6 +8101,14 @@ best_access_path(JOIN *join, Json_writer_object trace_wrapper(thd, "best_access_path"); DBUG_ENTER("best_access_path"); + /* + Assume that there is at least one accepted row from previous table combinations. + This fixes a problem when the selectivity for the preceding table combinations + becomes so high that record_count becomes << 1.0, which makes the cost for the + current table so low that it does not matter when calculating the best plans. + */ + set_if_bigger(record_count, 1.0); + best.cost= DBL_MAX; best.records= DBL_MAX; best.records_read= DBL_MAX; |