Commit 11881c42 authored by unknown's avatar unknown
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ha_innobase.cc: 

  Fix bug: MySQL could erroneously return Empty set if InnoDB estimated index range size to 0 records though the range was not empty; MySQL also failed to do the next-key locking in the case of an empty index range


sql/ha_innobase.cc:
  Fix bug: MySQL could erroneously return Empty set if InnoDB estimated index range size to 0 records though the range was not empty; MySQL also failed to do the next-key locking in the case of an empty index range
parent ae01a353

sql/ha_innobase.cc

+10 −0
Original line number Diff line number Diff line
@@ -3098,6 +3098,16 @@ ha_innobase::records_in_range( 


    	my_free((char*) key_val_buff2, MYF(0));



	/* The MySQL optimizer seems to believe an estimate of 0 rows is

	always accurate and may return the result 'Empty set' based on that.

	The accuracy is not guaranteed, and even if it were, for a locking

	read we should anyway perform the search to set the next-key lock.

	Add 1 to the value to make sure MySQL does not make the assumption! */



	if (n_rows == 0) {

	        n_rows = 1;

	}



	DBUG_RETURN((ha_rows) n_rows);

}