BUG#671340: Diverging results in with mrr_sort_keys=ON|OFF and join_cache_level=5

- Make Mrr_ordered_index_reader() save the rowid across scan interruptions

Also
- Fix compiler warning for setup_buffer_sizes()
- Add commented key_copy/key_restore for better handling of a similar issue
  with index record being destroyed by scan interruption (which causes 
  incorrect evaluation of pushed index condition later on).

mysql-test/r/innodb_mrr.result

@@ -576,3 +576,87 @@ count(*)
 480
 set join_cache_level= @my_save_join_cache_level;
 drop table t1;
+#
+# BUG#671340: Diverging results in with mrr_sort_keys=ON|OFF and join_cache_level=5
+#
+CREATE TABLE t1 (
+pk int(11) NOT NULL AUTO_INCREMENT,
+col_int_key int(11) NOT NULL,
+col_varchar_key varchar(1) NOT NULL,
+col_varchar_nokey varchar(1) NOT NULL,
+PRIMARY KEY (pk),
+KEY col_int_key (col_int_key),
+KEY col_varchar_key (col_varchar_key,col_int_key)
+) ENGINE=InnoDB;
+INSERT INTO t1 VALUES 
+(10,8,'v','v'),
+(11,8,'f','f'),
+(12,5,'v','v'),
+(13,8,'s','s'),
+(14,8,'a','a'),
+(15,6,'p','p'),
+(16,7,'z','z'),
+(17,2,'a','a'),
+(18,5,'h','h'),
+(19,7,'h','h'),
+(20,2,'v','v'),
+(21,9,'v','v'),
+(22,142,'b','b'),
+(23,3,'y','y'),
+(24,0,'v','v'),
+(25,3,'m','m'),
+(26,5,'z','z'),
+(27,9,'n','n'),
+(28,1,'d','d'),
+(29,107,'a','a');
+CREATE TABLE t2 (
+pk int(11) NOT NULL AUTO_INCREMENT,
+col_int_key int(11) NOT NULL,
+col_varchar_key varchar(1) NOT NULL,
+col_varchar_nokey varchar(1) NOT NULL,
+PRIMARY KEY (pk),
+KEY col_int_key (col_int_key),
+KEY col_varchar_key (col_varchar_key,col_int_key)
+) ENGINE=InnoDB;
+INSERT INTO t2 VALUES 
+(1,9,'x','x'),
+(2,5,'g','g'),
+(3,1,'o','o'),
+(4,0,'g','g'),
+(5,1,'v','v'),
+(6,190,'m','m'),
+(7,6,'x','x'),
+(8,3,'c','c'),
+(9,4,'z','z'),
+(10,3,'i','i'),
+(11,186,'x','x'),
+(12,1,'g','g'),
+(13,8,'q','q'),
+(14,226,'m','m'),
+(15,133,'p','p'),
+(16,6,'e','e'),
+(17,3,'t','t'),
+(18,8,'j','j'),
+(19,5,'h','h'),
+(20,7,'w','w');
+SELECT count(*), sum(table1.col_int_key*table2.pk) 
+FROM 
+t2 AS table1, t1 AS table2, t2 AS table3 
+WHERE 
+table3.col_varchar_nokey = table2.col_varchar_key AND table3.pk > table2.col_varchar_nokey ;
+count(*)	sum(table1.col_int_key*table2.pk)
+240	185955
+set @my_save_join_cache_level= @@join_cache_level;
+set @my_save_join_buffer_size= @@join_buffer_size;
+set join_cache_level=6;
+set join_buffer_size=1500;
+SELECT count(*), sum(table1.col_int_key*table2.pk) 
+FROM 
+t2 AS table1, t1 AS table2, t2 AS table3 
+WHERE 
+table3.col_varchar_nokey = table2.col_varchar_key AND table3.pk > table2.col_varchar_nokey ;
+count(*)	sum(table1.col_int_key*table2.pk)
+240	185955
+drop table t1,t2;
+set join_cache_level=@my_save_join_cache_level;
+set join_buffer_size=@my_save_join_buffer_size;

mysql-test/t/innodb_mrr.test

@@ -277,3 +277,90 @@ select count(*) from
 set join_cache_level= @my_save_join_cache_level;
 drop table t1;
 
+
+--echo #
+--echo # BUG#671340: Diverging results in with mrr_sort_keys=ON|OFF and join_cache_level=5
+--echo #
+CREATE TABLE t1 (
+  pk int(11) NOT NULL AUTO_INCREMENT,
+  col_int_key int(11) NOT NULL,
+  col_varchar_key varchar(1) NOT NULL,
+  col_varchar_nokey varchar(1) NOT NULL,
+  PRIMARY KEY (pk),
+  KEY col_int_key (col_int_key),
+  KEY col_varchar_key (col_varchar_key,col_int_key)
+) ENGINE=InnoDB;
+INSERT INTO t1 VALUES 
+  (10,8,'v','v'),
+  (11,8,'f','f'),
+  (12,5,'v','v'),
+  (13,8,'s','s'),
+  (14,8,'a','a'),
+  (15,6,'p','p'),
+  (16,7,'z','z'),
+  (17,2,'a','a'),
+  (18,5,'h','h'),
+  (19,7,'h','h'),
+  (20,2,'v','v'),
+  (21,9,'v','v'),
+  (22,142,'b','b'),
+  (23,3,'y','y'),
+  (24,0,'v','v'),
+  (25,3,'m','m'),
+  (26,5,'z','z'),
+  (27,9,'n','n'),
+  (28,1,'d','d'),
+  (29,107,'a','a');
+
+CREATE TABLE t2 (
+  pk int(11) NOT NULL AUTO_INCREMENT,
+  col_int_key int(11) NOT NULL,
+  col_varchar_key varchar(1) NOT NULL,
+  col_varchar_nokey varchar(1) NOT NULL,
+  PRIMARY KEY (pk),
+  KEY col_int_key (col_int_key),
+  KEY col_varchar_key (col_varchar_key,col_int_key)
+) ENGINE=InnoDB;
+INSERT INTO t2 VALUES 
+  (1,9,'x','x'),
+  (2,5,'g','g'),
+  (3,1,'o','o'),
+  (4,0,'g','g'),
+  (5,1,'v','v'),
+  (6,190,'m','m'),
+  (7,6,'x','x'),
+  (8,3,'c','c'),
+  (9,4,'z','z'),
+  (10,3,'i','i'),
+  (11,186,'x','x'),
+  (12,1,'g','g'),
+  (13,8,'q','q'),
+  (14,226,'m','m'),
+  (15,133,'p','p'),
+  (16,6,'e','e'),
+  (17,3,'t','t'),
+  (18,8,'j','j'),
+  (19,5,'h','h'),
+  (20,7,'w','w');
+
+SELECT count(*), sum(table1.col_int_key*table2.pk) 
+FROM 
+  t2 AS table1, t1 AS table2, t2 AS table3 
+WHERE 
+  table3.col_varchar_nokey = table2.col_varchar_key AND table3.pk > table2.col_varchar_nokey ;
+
+set @my_save_join_cache_level= @@join_cache_level;
+set @my_save_join_buffer_size= @@join_buffer_size;
+set join_cache_level=6;
+set join_buffer_size=1500;
+
+SELECT count(*), sum(table1.col_int_key*table2.pk) 
+FROM 
+  t2 AS table1, t1 AS table2, t2 AS table3 
+WHERE 
+  table3.col_varchar_nokey = table2.col_varchar_key AND table3.pk > table2.col_varchar_nokey ;
+
+drop table t1,t2;
+set join_cache_level=@my_save_join_cache_level;
+set join_buffer_size=@my_save_join_buffer_size;
+

sql/multi_range_read.cc

@@ -372,6 +372,42 @@ int Mrr_ordered_index_reader::get_next(char **range_info)
   DBUG_RETURN(0);
 }
 
+void Mrr_ordered_index_reader::set_temp_space(uchar *space)
+{
+  //saved_key_tuple= space;
+  saved_rowid= space;
+  have_saved_rowid= FALSE;
+}
+
+void Mrr_ordered_index_reader::interrupt_read()
+{
+  /*
+  key_copy(saved_key_tuple, file->get_table()->record[0], 
+           &file->get_table()->key_info[file->active_index],
+           keypar.key_tuple_length);
+  */
+  /* Save the last rowid */
+  memcpy(saved_rowid, file->ref, file->ref_length);
+  have_saved_rowid= TRUE;
+}
+
+void Mrr_ordered_index_reader::position()
+{
+  if (have_saved_rowid)
+    memcpy(file->ref, saved_rowid, file->ref_length);
+  else
+    Mrr_index_reader::position();
+}
+
+void Mrr_ordered_index_reader::resume_read()
+{
+  /*
+  key_restore(file->get_table()->record[0], saved_key_tuple, 
+              &file->get_table()->key_info[file->active_index],
+              keypar.key_tuple_length);
+  */
+}
+
 
 /**
   Fill the buffer with (lookup_tuple, range_id) pairs and sort
@@ -480,6 +516,8 @@ int Mrr_ordered_index_reader::init(handler *h_arg, RANGE_SEQ_IF *seq_funcs,
 
   */
   disallow_identical_key_handling= test(mrr_funcs.skip_index_tuple);
+  /*bzero(saved_key_tuple, keypar.key_tuple_length);*/
+  have_saved_rowid= FALSE;
   return 0;
 }
 
@@ -571,6 +609,7 @@ int Mrr_ordered_rndpos_reader::refill_from_index_reader()
 
   last_identical_rowid= NULL;
 
+  index_reader->resume_read();
   while (rowid_buffer->can_write())
   {
     res= index_reader->get_next(&range_info);
@@ -589,6 +628,7 @@ int Mrr_ordered_rndpos_reader::refill_from_index_reader()
     rowid_buffer->write();
   }
    
+  index_reader->interrupt_read();
   /* Sort the buffer contents by rowid */
   rowid_buffer->sort((qsort2_cmp)rowid_cmp_reverse, (void*)file);
 
@@ -788,6 +828,16 @@ int DsMrr_impl::dsmrr_init(handler *h_arg, RANGE_SEQ_IF *seq_funcs,
     keypar.key_size_in_keybuf= keypar.use_key_pointers? 
                                  sizeof(char*) : keypar.key_tuple_length;
     key_buff_elem_size= keypar.key_size_in_keybuf + (int)is_mrr_assoc * sizeof(void*);
+    
+    /* Ordered index reader needs some space to store an index tuple */
+    if (strategy != index_strategy)
+    {
+      if (full_buf_end - full_buf <= (ptrdiff_t)primary_file->ref_length/*keypar.key_tuple_length*/)
+        goto use_default_impl;
+      reader_factory.ordered_index_reader.set_temp_space(full_buf);
+      //full_buf += keypar.key_tuple_length;
+      full_buf += primary_file->ref_length;
+    }
   }
 
   if (strategy == index_strategy)
@@ -1039,7 +1089,7 @@ int Mrr_ordered_index_reader::compare_keys_reverse(void* arg, uchar* key1,
 bool DsMrr_impl::setup_buffer_sharing(uint key_size_in_keybuf, 
                                       key_part_map key_tuple_map)
 {
-  uint key_buff_elem_size= key_size_in_keybuf + 
+  long key_buff_elem_size= key_size_in_keybuf + 
                            (int)is_mrr_assoc * sizeof(void*);
   
   KEY *key_info= &primary_file->get_table()->key_info[keyno];
@@ -1186,6 +1236,7 @@ int Key_value_records_iterator::init(Mrr_ordered_index_reader *owner_arg)
     move_to_next_key_value();
     return res;
   }
+  owner->have_saved_rowid= FALSE;
   get_next_row= FALSE;
   return 0;
 }
@@ -1212,6 +1263,7 @@ int Key_value_records_iterator::get_next()
       return res; 
     }
     identical_key_it.init(owner->key_buffer);
+    owner->have_saved_rowid= FALSE;
     get_next_row= FALSE;
   }
 

sql/multi_range_read.h

@@ -211,8 +211,11 @@ public:
   /* Get pointer to place where every get_next() call will put rowid */
   virtual uchar *get_rowid_ptr() = 0;
   /* Get the rowid (call this after get_next() call) */
-  void position();
+  virtual void position();
   virtual bool skip_record(char *range_id, uchar *rowid) = 0;
+
+  virtual void interrupt_read() {}
+  virtual void resume_read() {}
 };
 
 
@@ -269,6 +272,10 @@ public:
             mrr_funcs.skip_index_tuple(mrr_iter, range_info));
   }
 
+  void set_temp_space(uchar *space);
+  void interrupt_read();
+  void resume_read();
+  void position();
 private:
   Key_value_records_iterator kv_it;
 
@@ -300,6 +307,11 @@ private:
   
   /* TRUE == reached eof when enumerating ranges */
   bool source_exhausted;
+  
+  /* TODO */
+  /*uchar *saved_key_tuple;*/
+  uchar *saved_rowid;
+  bool have_saved_rowid;
 
   static int compare_keys(void* arg, uchar* key1, uchar* key2);
   static int compare_keys_reverse(void* arg, uchar* key1, uchar* key2);