MDEV-27062: Make histogram_type=JSON_HB the new default

mysql-test/main/derived_cond_pushdown.result

@@ -18387,7 +18387,7 @@ explain extended select t2.a,t2.b,t2.c,t.c as t_c,t.max,t.min
 from t2, t3, (select c, max(b) max, min(b) min from t4 group by c) t
 where t2.b < 40 and t2.a=t3.a and t3.c=t.c;
 id	select_type	table	type	possible_keys	key	key_len	ref	rows	filtered	Extra
-1	PRIMARY	t2	ALL	NULL	NULL	NULL	NULL	90	63.28	Using where
+1	PRIMARY	t2	ALL	NULL	NULL	NULL	NULL	90	53.33	Using where
 1	PRIMARY	t3	ref	idx_a	idx_a	5	test.t2.a	1	100.00	Using where
 1	PRIMARY	<derived2>	ref	key0	key0	128	test.t3.c	10	100.00	
 2	DERIVED	t4	ALL	idx_c	NULL	NULL	NULL	160	100.00	Using temporary; Using filesort
@@ -18406,7 +18406,7 @@ EXPLAIN
           "table_name": "t2",
           "access_type": "ALL",
           "rows": 90,
-          "filtered": 63.28125,
+          "filtered": 53.33333206,
           "attached_condition": "t2.b < 40 and t2.a is not null"
         }
       },
@@ -18910,7 +18910,7 @@ explain extended select *
 from t2, t3, (select c, b, sum(b) over (partition by c) from t4 ) t
 where t2.b < 40 and t2.a=t3.a and t3.c=t.c;
 id	select_type	table	type	possible_keys	key	key_len	ref	rows	filtered	Extra
-1	PRIMARY	t2	ALL	NULL	NULL	NULL	NULL	90	63.28	Using where
+1	PRIMARY	t2	ALL	NULL	NULL	NULL	NULL	90	53.33	Using where
 1	PRIMARY	t3	ref	idx_a	idx_a	5	test.t2.a	1	100.00	Using where
 1	PRIMARY	<derived2>	ref	key0	key0	128	test.t3.c	10	100.00	
 2	DERIVED	t4	ALL	idx_c	NULL	NULL	NULL	160	100.00	Using temporary
@@ -18929,7 +18929,7 @@ EXPLAIN
           "table_name": "t2",
           "access_type": "ALL",
           "rows": 90,
-          "filtered": 63.28125,
+          "filtered": 53.33333206,
           "attached_condition": "t2.b < 40 and t2.a is not null"
         }
       },

mysql-test/main/group_min_max.result

@@ -2080,19 +2080,19 @@ id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
 explain extended select a1,a2,min(b),max(b) from t1
 where (a1 = 'b' or a1 = 'd' or a1 = 'a' or a1 = 'c') and (a2 > 'a') and (c > 'a111') group by a1,a2;
 id	select_type	table	type	possible_keys	key	key_len	ref	rows	filtered	Extra
-1	SIMPLE	t1	range	idx_t1_0,idx_t1_1,idx_t1_2	idx_t1_1	130	NULL	276	99.22	Using where; Using index
+1	SIMPLE	t1	range	idx_t1_0,idx_t1_1,idx_t1_2	idx_t1_1	130	NULL	276	98.44	Using where; Using index
 Warnings:
 Note	1003	select `test`.`t1`.`a1` AS `a1`,`test`.`t1`.`a2` AS `a2`,min(`test`.`t1`.`b`) AS `min(b)`,max(`test`.`t1`.`b`) AS `max(b)` from `test`.`t1` where (`test`.`t1`.`a1` = 'b' or `test`.`t1`.`a1` = 'd' or `test`.`t1`.`a1` = 'a' or `test`.`t1`.`a1` = 'c') and `test`.`t1`.`a2` > 'a' and `test`.`t1`.`c` > 'a111' group by `test`.`t1`.`a1`,`test`.`t1`.`a2`
 explain extended select a1,a2,b,min(c),max(c) from t1
 where (a1 = 'b' or a1 = 'd' or a1 = 'a' or a1 = 'c') and (a2 > 'a') and (d > 'xy2') group by a1,a2,b;
 id	select_type	table	type	possible_keys	key	key_len	ref	rows	filtered	Extra
-1	SIMPLE	t1	ALL	idx_t1_0,idx_t1_1,idx_t1_2	NULL	NULL	NULL	512	40.43	Using where; Using temporary; Using filesort
+1	SIMPLE	t1	ALL	idx_t1_0,idx_t1_1,idx_t1_2	NULL	NULL	NULL	512	26.95	Using where; Using temporary; Using filesort
 Warnings:
 Note	1003	select `test`.`t1`.`a1` AS `a1`,`test`.`t1`.`a2` AS `a2`,`test`.`t1`.`b` AS `b`,min(`test`.`t1`.`c`) AS `min(c)`,max(`test`.`t1`.`c`) AS `max(c)` from `test`.`t1` where (`test`.`t1`.`a1` = 'b' or `test`.`t1`.`a1` = 'd' or `test`.`t1`.`a1` = 'a' or `test`.`t1`.`a1` = 'c') and `test`.`t1`.`a2` > 'a' and `test`.`t1`.`d` > 'xy2' group by `test`.`t1`.`a1`,`test`.`t1`.`a2`,`test`.`t1`.`b`
 explain extended select a1,a2,b,c from t1
 where (a1 = 'b' or a1 = 'd' or a1 = 'a' or a1 = 'c') and (a2 > 'a') and (d > 'xy2') group by a1,a2,b,c;
 id	select_type	table	type	possible_keys	key	key_len	ref	rows	filtered	Extra
-1	SIMPLE	t1	ALL	idx_t1_0,idx_t1_1,idx_t1_2	NULL	NULL	NULL	512	40.43	Using where; Using temporary; Using filesort
+1	SIMPLE	t1	ALL	idx_t1_0,idx_t1_1,idx_t1_2	NULL	NULL	NULL	512	26.95	Using where; Using temporary; Using filesort
 Warnings:
 Note	1003	select `test`.`t1`.`a1` AS `a1`,`test`.`t1`.`a2` AS `a2`,`test`.`t1`.`b` AS `b`,`test`.`t1`.`c` AS `c` from `test`.`t1` where (`test`.`t1`.`a1` = 'b' or `test`.`t1`.`a1` = 'd' or `test`.`t1`.`a1` = 'a' or `test`.`t1`.`a1` = 'c') and `test`.`t1`.`a2` > 'a' and `test`.`t1`.`d` > 'xy2' group by `test`.`t1`.`a1`,`test`.`t1`.`a2`,`test`.`t1`.`b`,`test`.`t1`.`c`
 explain select a1,a2,b,max(c),min(c) from t2 where (a2 = 'a') and (b = 'b') or (b < 'b') group by a1;
@@ -2100,7 +2100,7 @@ id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
 1	SIMPLE	t2	index	NULL	idx_t2_1	163	NULL	548	Using where; Using index
 explain extended select a1,a2,b from t1 where (a1 = 'b' or a1 = 'd' or a1 = 'a' or a1 = 'c') and (a2 > 'a') and (c > 'a111') group by a1,a2,b;
 id	select_type	table	type	possible_keys	key	key_len	ref	rows	filtered	Extra
-1	SIMPLE	t1	range	idx_t1_0,idx_t1_1,idx_t1_2	idx_t1_1	130	NULL	276	99.22	Using where; Using index
+1	SIMPLE	t1	range	idx_t1_0,idx_t1_1,idx_t1_2	idx_t1_1	130	NULL	276	98.44	Using where; Using index
 Warnings:
 Note	1003	select `test`.`t1`.`a1` AS `a1`,`test`.`t1`.`a2` AS `a2`,`test`.`t1`.`b` AS `b` from `test`.`t1` where (`test`.`t1`.`a1` = 'b' or `test`.`t1`.`a1` = 'd' or `test`.`t1`.`a1` = 'a' or `test`.`t1`.`a1` = 'c') and `test`.`t1`.`a2` > 'a' and `test`.`t1`.`c` > 'a111' group by `test`.`t1`.`a1`,`test`.`t1`.`a2`,`test`.`t1`.`b`
 explain select a1,a2,min(b),c from t2 where (a2 = 'a') and (c = 'a111') group by a1;

mysql-test/main/join_cache.result

@@ -6220,7 +6220,7 @@ EXPLAIN
             "key_length": "10",
             "used_key_parts": ["kp1", "kp2"],
             "rows": 836,
-            "filtered": 76.43428802,
+            "filtered": 76,
             "index_condition": "b.kp2 <= 10",
             "attached_condition": "b.kp2 <= 10 and b.col1 + 1 < 33333"
           },

mysql-test/main/join_outer.result

@@ -2795,7 +2795,7 @@ test.t3	analyze	status	OK
 explain extended select * from t1 left join t3 on t1.a=t3.b and t3.a<5;
 id	select_type	table	type	possible_keys	key	key_len	ref	rows	filtered	Extra
 1	SIMPLE	t1	ALL	NULL	NULL	NULL	NULL	10	100.00	
-1	SIMPLE	t3	ALL	NULL	NULL	NULL	NULL	1000	1.96	Using where
+1	SIMPLE	t3	ALL	NULL	NULL	NULL	NULL	1000	0.50	Using where
 Warnings:
 Note	1003	select `test`.`t1`.`a` AS `a`,`test`.`t3`.`a` AS `a`,`test`.`t3`.`b` AS `b` from `test`.`t1` left join `test`.`t3` on(`test`.`t3`.`b` = `test`.`t1`.`a` and `test`.`t3`.`a` < 5) where 1
 # t3.filtered must less than 100%, too:
@@ -2803,7 +2803,7 @@ explain extended select * from t1 left join (t3 join t2) on t1.a=t3.b and t3.a<5
 id	select_type	table	type	possible_keys	key	key_len	ref	rows	filtered	Extra
 1	SIMPLE	t1	ALL	NULL	NULL	NULL	NULL	10	100.00	
 1	SIMPLE	t2	ALL	NULL	NULL	NULL	NULL	2	100.00	
-1	SIMPLE	t3	ALL	NULL	NULL	NULL	NULL	1000	1.96	Using where
+1	SIMPLE	t3	ALL	NULL	NULL	NULL	NULL	1000	0.50	Using where
 Warnings:
 Note	1003	select `test`.`t1`.`a` AS `a`,`test`.`t3`.`a` AS `a`,`test`.`t3`.`b` AS `b`,`test`.`t2`.`a` AS `a` from `test`.`t1` left join (`test`.`t3` join `test`.`t2`) on(`test`.`t3`.`b` = `test`.`t1`.`a` and `test`.`t3`.`a` < 5) where 1
 drop table t1,t2,t3;

mysql-test/main/join_outer_jcl6.result

@@ -2802,7 +2802,7 @@ test.t3	analyze	status	OK
 explain extended select * from t1 left join t3 on t1.a=t3.b and t3.a<5;
 id	select_type	table	type	possible_keys	key	key_len	ref	rows	filtered	Extra
 1	SIMPLE	t1	ALL	NULL	NULL	NULL	NULL	10	100.00	
-1	SIMPLE	t3	hash_ALL	NULL	#hash#$hj	5	test.t1.a	1000	1.96	Using where; Using join buffer (flat, BNLH join)
+1	SIMPLE	t3	hash_ALL	NULL	#hash#$hj	5	test.t1.a	1000	0.50	Using where; Using join buffer (flat, BNLH join)
 Warnings:
 Note	1003	select `test`.`t1`.`a` AS `a`,`test`.`t3`.`a` AS `a`,`test`.`t3`.`b` AS `b` from `test`.`t1` left join `test`.`t3` on(`test`.`t3`.`b` = `test`.`t1`.`a` and `test`.`t3`.`a` < 5 and `test`.`t1`.`a` is not null) where 1
 # t3.filtered must less than 100%, too:
@@ -2810,7 +2810,7 @@ explain extended select * from t1 left join (t3 join t2) on t1.a=t3.b and t3.a<5
 id	select_type	table	type	possible_keys	key	key_len	ref	rows	filtered	Extra
 1	SIMPLE	t1	ALL	NULL	NULL	NULL	NULL	10	100.00	
 1	SIMPLE	t2	ALL	NULL	NULL	NULL	NULL	2	100.00	Using where; Using join buffer (flat, BNL join)
-1	SIMPLE	t3	hash_ALL	NULL	#hash#$hj	5	test.t1.a	1000	1.96	Using where; Using join buffer (incremental, BNLH join)
+1	SIMPLE	t3	hash_ALL	NULL	#hash#$hj	5	test.t1.a	1000	0.50	Using where; Using join buffer (incremental, BNLH join)
 Warnings:
 Note	1003	select `test`.`t1`.`a` AS `a`,`test`.`t3`.`a` AS `a`,`test`.`t3`.`b` AS `b`,`test`.`t2`.`a` AS `a` from `test`.`t1` left join (`test`.`t3` join `test`.`t2`) on(`test`.`t3`.`b` = `test`.`t1`.`a` and `test`.`t3`.`a` < 5 and `test`.`t1`.`a` is not null) where 1
 drop table t1,t2,t3;

mysql-test/main/mysqld--help.result

@@ -1551,7 +1551,7 @@ gtid-pos-auto-engines
 gtid-strict-mode FALSE
 help TRUE
 histogram-size 254
-histogram-type DOUBLE_PREC_HB
+histogram-type JSON_HB
 host-cache-size 279
 idle-readonly-transaction-timeout 0
 idle-transaction-timeout 0

mysql-test/main/opt_trace.result

@@ -2091,12 +2091,12 @@ explain  select * from t1 where a=1 and b=2 order by c limit 1	{
                   {
                     "column_name": "a",
                     "ranges": ["1 <= a <= 1"],
-                    "selectivity_from_histogram": 0.1796875
+                    "selectivity_from_histogram": 0.181
                   },
                   {
                     "column_name": "b",
                     "ranges": ["2 <= b <= 2"],
-                    "selectivity_from_histogram": 0.015625
+                    "selectivity_from_histogram": 0.021
                   }
                 ],
                 "cond_selectivity": 0.021
@@ -8083,20 +8083,20 @@ JSON_DETAILED(JSON_EXTRACT(trace, '$**.considered_execution_plans'))
                     
                     {
                         "access_type": "scan",
-                        "resulting_rows": 5.9375,
-                        "cost": 2.829589844,
+                        "resulting_rows": 4,
+                        "cost": 3.217089844,
                         "chosen": true
                     }
                 ],
                 "chosen_access_method": 
                 {
                     "type": "scan",
-                    "records": 5.9375,
-                    "cost": 2.829589844,
+                    "records": 4,
+                    "cost": 3.217089844,
                     "uses_join_buffering": false
                 }
             },
-            "rows_for_plan": 5.9375,
+            "rows_for_plan": 4,
             "cost_for_plan": 4.017089844,
             "rest_of_plan": 
             [
@@ -8114,22 +8114,22 @@ JSON_DETAILED(JSON_EXTRACT(trace, '$**.considered_execution_plans'))
                             
                             {
                                 "access_type": "scan",
-                                "resulting_rows": 804.6875,
-                                "cost": 256.8548584,
+                                "resulting_rows": 800,
+                                "cost": 176.7890625,
                                 "chosen": true
                             }
                         ],
                         "chosen_access_method": 
                         {
                             "type": "scan",
-                            "records": 804.6875,
-                            "cost": 256.8548584,
+                            "records": 800,
+                            "cost": 176.7890625,
                             "uses_join_buffering": false
                         }
                     },
-                    "rows_for_plan": 4777.832031,
-                    "cost_for_plan": 1216.438354,
-                    "estimated_join_cardinality": 4777.832031
+                    "rows_for_plan": 3200,
+                    "cost_for_plan": 820.8061523,
+                    "estimated_join_cardinality": 3200
                 }
             ]
         },
@@ -8146,20 +8146,20 @@ JSON_DETAILED(JSON_EXTRACT(trace, '$**.considered_execution_plans'))
                     
                     {
                         "access_type": "scan",
-                        "resulting_rows": 804.6875,
-                        "cost": 43.25976562,
+                        "resulting_rows": 800,
+                        "cost": 44.19726562,
                         "chosen": true
                     }
                 ],
                 "chosen_access_method": 
                 {
                     "type": "scan",
-                    "records": 804.6875,
-                    "cost": 43.25976562,
+                    "records": 800,
+                    "cost": 44.19726562,
                     "uses_join_buffering": false
                 }
             },
-            "rows_for_plan": 804.6875,
+            "rows_for_plan": 800,
             "cost_for_plan": 204.1972656,
             "pruned_by_heuristic": true
         }
@@ -8230,8 +8230,8 @@ JSON_DETAILED(JSON_EXTRACT(trace, '$**.considered_execution_plans'))
                             
                             {
                                 "access_type": "scan",
-                                "resulting_rows": 804.6875,
-                                "cost": 43.25976562,
+                                "resulting_rows": 800,
+                                "cost": 44.19726562,
                                 "chosen": false
                             }
                         ],
@@ -8245,8 +8245,8 @@ JSON_DETAILED(JSON_EXTRACT(trace, '$**.considered_execution_plans'))
                     },
                     "rows_for_plan": 10,
                     "cost_for_plan": 26.02294779,
-                    "selectivity": 0.8046875,
-                    "estimated_join_cardinality": 8.046875
+                    "selectivity": 0.8,
+                    "estimated_join_cardinality": 8
                 }
             ]
         },
@@ -8263,20 +8263,20 @@ JSON_DETAILED(JSON_EXTRACT(trace, '$**.considered_execution_plans'))
                     
                     {
                         "access_type": "scan",
-                        "resulting_rows": 804.6875,
-                        "cost": 43.25976562,
+                        "resulting_rows": 800,
+                        "cost": 44.19726562,
                         "chosen": true
                     }
                 ],
                 "chosen_access_method": 
                 {
                     "type": "scan",
-                    "records": 804.6875,
-                    "cost": 43.25976562,
+                    "records": 800,
+                    "cost": 44.19726562,
                     "uses_join_buffering": false
                 }
             },
-            "rows_for_plan": 804.6875,
+            "rows_for_plan": 800,
             "cost_for_plan": 204.1972656,
             "pruned_by_cost": true
         }
@@ -8564,7 +8564,7 @@ test.t1	analyze	status	Engine-independent statistics collected
 test.t1	analyze	status	OK
 EXPLAIN EXTENDED SELECT * from t1 WHERE a between 1 and 5 and b <= 5;
 id	select_type	table	type	possible_keys	key	key_len	ref	rows	filtered	Extra
-1	SIMPLE	t1	ALL	NULL	NULL	NULL	NULL	100	0.22	Using where
+1	SIMPLE	t1	ALL	NULL	NULL	NULL	NULL	100	0.25	Using where
 Warnings:
 Note	1003	select `test`.`t1`.`a` AS `a`,`test`.`t1`.`b` AS `b` from `test`.`t1` where `test`.`t1`.`a` between 1 and 5 and `test`.`t1`.`b` <= 5
 select JSON_DETAILED(JSON_EXTRACT(trace, '$**.selectivity_for_columns')) from INFORMATION_SCHEMA.OPTIMIZER_TRACE;
@@ -8579,7 +8579,7 @@ JSON_DETAILED(JSON_EXTRACT(trace, '$**.selectivity_for_columns'))
             [
                 "1 <= a <= 5"
             ],
-            "selectivity_from_histogram": 0.046875
+            "selectivity_from_histogram": 0.05
         },
         
         {
@@ -8588,13 +8588,13 @@ JSON_DETAILED(JSON_EXTRACT(trace, '$**.selectivity_for_columns'))
             [
                 "NULL < b <= 5"
             ],
-            "selectivity_from_histogram": 0.046875
+            "selectivity_from_histogram": 0.05
         }
     ]
 ]
 EXPLAIN EXTENDED SELECT * from t1 WHERE a != 5;
 id	select_type	table	type	possible_keys	key	key_len	ref	rows	filtered	Extra
-1	SIMPLE	t1	ALL	NULL	NULL	NULL	NULL	100	100.00	Using where
+1	SIMPLE	t1	ALL	NULL	NULL	NULL	NULL	100	98.00	Using where
 Warnings:
 Note	1003	select `test`.`t1`.`a` AS `a`,`test`.`t1`.`b` AS `b` from `test`.`t1` where `test`.`t1`.`a` <> 5
 select JSON_DETAILED(JSON_EXTRACT(trace, '$**.selectivity_for_columns')) from INFORMATION_SCHEMA.OPTIMIZER_TRACE;
@@ -8610,13 +8610,13 @@ JSON_DETAILED(JSON_EXTRACT(trace, '$**.selectivity_for_columns'))
                 "NULL < a < 5",
                 "5 < a"
             ],
-            "selectivity_from_histogram": 1
+            "selectivity_from_histogram": 0.98
         }
     ]
 ]
 EXPLAIN EXTENDED SELECT * from t1 WHERE b >= 10 and b < 25;
 id	select_type	table	type	possible_keys	key	key_len	ref	rows	filtered	Extra
-1	SIMPLE	t1	ALL	NULL	NULL	NULL	NULL	100	15.62	Using where
+1	SIMPLE	t1	ALL	NULL	NULL	NULL	NULL	100	14.00	Using where
 Warnings:
 Note	1003	select `test`.`t1`.`a` AS `a`,`test`.`t1`.`b` AS `b` from `test`.`t1` where `test`.`t1`.`b` >= 10 and `test`.`t1`.`b` < 25
 select JSON_DETAILED(JSON_EXTRACT(trace, '$**.selectivity_for_columns')) from INFORMATION_SCHEMA.OPTIMIZER_TRACE;
@@ -8631,7 +8631,7 @@ JSON_DETAILED(JSON_EXTRACT(trace, '$**.selectivity_for_columns'))
             [
                 "10 <= b < 25"
             ],
-            "selectivity_from_histogram": 0.15625
+            "selectivity_from_histogram": 0.14
         }
     ]
 ]

mysql-test/main/partition.result

@@ -2741,7 +2741,7 @@ id	select_type	table	partitions	type	possible_keys	key	key_len	ref	rows	Extra
 1	SIMPLE	t2	p1,p2	ALL	NULL	NULL	NULL	NULL	400	Using where
 explain extended select * from t2 where b=5;
 id	select_type	table	type	possible_keys	key	key_len	ref	rows	filtered	Extra
-1	SIMPLE	t2	ALL	NULL	NULL	NULL	NULL	1000	19.61	Using where
+1	SIMPLE	t2	ALL	NULL	NULL	NULL	NULL	1000	0.10	Using where
 Warnings:
 Note	1003	select `test`.`t2`.`part_key` AS `part_key`,`test`.`t2`.`a` AS `a`,`test`.`t2`.`b` AS `b` from `test`.`t2` where `test`.`t2`.`b` = 5
 explain partitions select * from t2 where b=5;
@@ -2749,7 +2749,7 @@ id	select_type	table	partitions	type	possible_keys	key	key_len	ref	rows	Extra
 1	SIMPLE	t2	p0,p1,p2,p3,p4	ALL	NULL	NULL	NULL	NULL	1000	Using where
 explain extended select * from t2 partition(p0)  where b=1;
 id	select_type	table	type	possible_keys	key	key_len	ref	rows	filtered	Extra
-1	SIMPLE	t2	ALL	NULL	NULL	NULL	NULL	200	19.61	Using where
+1	SIMPLE	t2	ALL	NULL	NULL	NULL	NULL	200	20.00	Using where
 Warnings:
 Note	1003	select `test`.`t2`.`part_key` AS `part_key`,`test`.`t2`.`a` AS `a`,`test`.`t2`.`b` AS `b` from `test`.`t2` PARTITION (`p0`) where `test`.`t2`.`b` = 1
 set @@use_stat_tables= @save_use_stat_tables;

mysql-test/main/selectivity.result

@@ -1372,14 +1372,14 @@ test.t2	analyze	status	Table is already up to date
 explain extended 
 select * from t1 straight_join t2 where t1.a=t2.a and t1.a<10;
 id	select_type	table	type	possible_keys	key	key_len	ref	rows	filtered	Extra
-1	SIMPLE	t1	ALL	NULL	NULL	NULL	NULL	1000	1.96	Using where
+1	SIMPLE	t1	ALL	NULL	NULL	NULL	NULL	1000	1.00	Using where
 1	SIMPLE	t2	ref	a	a	5	test.t1.a	10	100.00	
 Warnings:
 Note	1003	select `test`.`t1`.`a` AS `a`,`test`.`t2`.`a` AS `a`,`test`.`t2`.`b` AS `b` from `test`.`t1` straight_join `test`.`t2` where `test`.`t2`.`a` = `test`.`t1`.`a` and `test`.`t1`.`a` < 10
 explain extended 
 select * from t1 straight_join t2 where t1.a=t2.a and t2.a<10;
 id	select_type	table	type	possible_keys	key	key_len	ref	rows	filtered	Extra
-1	SIMPLE	t1	ALL	NULL	NULL	NULL	NULL	1000	1.96	Using where
+1	SIMPLE	t1	ALL	NULL	NULL	NULL	NULL	1000	1.00	Using where
 1	SIMPLE	t2	ref	a	a	5	test.t1.a	10	100.00	
 Warnings:
 Note	1003	select `test`.`t1`.`a` AS `a`,`test`.`t2`.`a` AS `a`,`test`.`t2`.`b` AS `b` from `test`.`t1` straight_join `test`.`t2` where `test`.`t2`.`a` = `test`.`t1`.`a` and `test`.`t1`.`a` < 10
@@ -1649,12 +1649,12 @@ test.t1	analyze	status	Table is already up to date
 # Check what info the optimizer has about selectivities
 explain extended select * from t1 use index () where a in (17,51,5);
 id	select_type	table	type	possible_keys	key	key_len	ref	rows	filtered	Extra
-1	SIMPLE	t1	ALL	NULL	NULL	NULL	NULL	1000	3.90	Using where
+1	SIMPLE	t1	ALL	NULL	NULL	NULL	NULL	1000	2.90	Using where
 Warnings:
 Note	1003	select `test`.`t1`.`a` AS `a`,`test`.`t1`.`b` AS `b` from `test`.`t1` USE INDEX () where `test`.`t1`.`a` in (17,51,5)
 explain extended select * from t1 use index () where b=2;
 id	select_type	table	type	possible_keys	key	key_len	ref	rows	filtered	Extra
-1	SIMPLE	t1	ALL	NULL	NULL	NULL	NULL	1000	5.47	Using where
+1	SIMPLE	t1	ALL	NULL	NULL	NULL	NULL	1000	5.90	Using where
 Warnings:
 Note	1003	select `test`.`t1`.`a` AS `a`,`test`.`t1`.`b` AS `b` from `test`.`t1` USE INDEX () where `test`.`t1`.`b` = 2
 # Now, the equality is used for ref access, while the range condition
@@ -1895,7 +1895,7 @@ test.t1	analyze	status	Engine-independent statistics collected
 test.t1	analyze	status	OK
 EXPLAIN EXTENDED SELECT * from t1 where t1.a >= 81;
 id	select_type	table	type	possible_keys	key	key_len	ref	rows	filtered	Extra
-1	SIMPLE	t1	ALL	NULL	NULL	NULL	NULL	3	66.41	Using where
+1	SIMPLE	t1	ALL	NULL	NULL	NULL	NULL	3	66.67	Using where
 Warnings:
 Note	1003	select `test`.`t1`.`a` AS `a`,`test`.`t1`.`b` AS `b` from `test`.`t1` where `test`.`t1`.`a` >= 81
 SELECT HEX(a), b from t1 where t1.a >= 81;
@@ -1919,7 +1919,7 @@ test.t1	analyze	status	Engine-independent statistics collected
 test.t1	analyze	status	OK
 EXPLAIN EXTENDED SELECT * FROM t1 WHERE a=2;
 id	select_type	table	type	possible_keys	key	key_len	ref	rows	filtered	Extra
-1	SIMPLE	t1	ALL	NULL	NULL	NULL	NULL	5	39.84	Using where
+1	SIMPLE	t1	ALL	NULL	NULL	NULL	NULL	5	40.00	Using where
 Warnings:
 Note	1003	select `test`.`t1`.`a` AS `a` from `test`.`t1` where `test`.`t1`.`a` = 2
 SET optimizer_use_condition_selectivity=3;

mysql-test/main/selectivity_innodb.result

@@ -1384,14 +1384,14 @@ test.t2	analyze	status	OK
 explain extended 
 select * from t1 straight_join t2 where t1.a=t2.a and t1.a<10;
 id	select_type	table	type	possible_keys	key	key_len	ref	rows	filtered	Extra
-1	SIMPLE	t1	ALL	NULL	NULL	NULL	NULL	1000	1.96	Using where
+1	SIMPLE	t1	ALL	NULL	NULL	NULL	NULL	1000	1.00	Using where
 1	SIMPLE	t2	ref	a	a	5	test.t1.a	10	100.00	
 Warnings:
 Note	1003	select `test`.`t1`.`a` AS `a`,`test`.`t2`.`a` AS `a`,`test`.`t2`.`b` AS `b` from `test`.`t1` straight_join `test`.`t2` where `test`.`t2`.`a` = `test`.`t1`.`a` and `test`.`t1`.`a` < 10
 explain extended 
 select * from t1 straight_join t2 where t1.a=t2.a and t2.a<10;
 id	select_type	table	type	possible_keys	key	key_len	ref	rows	filtered	Extra
-1	SIMPLE	t1	ALL	NULL	NULL	NULL	NULL	1000	1.96	Using where
+1	SIMPLE	t1	ALL	NULL	NULL	NULL	NULL	1000	1.00	Using where
 1	SIMPLE	t2	ref	a	a	5	test.t1.a	10	100.00	
 Warnings:
 Note	1003	select `test`.`t1`.`a` AS `a`,`test`.`t2`.`a` AS `a`,`test`.`t2`.`b` AS `b` from `test`.`t1` straight_join `test`.`t2` where `test`.`t2`.`a` = `test`.`t1`.`a` and `test`.`t1`.`a` < 10
@@ -1661,12 +1661,12 @@ test.t1	analyze	status	OK
 # Check what info the optimizer has about selectivities
 explain extended select * from t1 use index () where a in (17,51,5);
 id	select_type	table	type	possible_keys	key	key_len	ref	rows	filtered	Extra
-1	SIMPLE	t1	ALL	NULL	NULL	NULL	NULL	1000	3.90	Using where
+1	SIMPLE	t1	ALL	NULL	NULL	NULL	NULL	1000	2.90	Using where
 Warnings:
 Note	1003	select `test`.`t1`.`a` AS `a`,`test`.`t1`.`b` AS `b` from `test`.`t1` USE INDEX () where `test`.`t1`.`a` in (17,51,5)
 explain extended select * from t1 use index () where b=2;
 id	select_type	table	type	possible_keys	key	key_len	ref	rows	filtered	Extra
-1	SIMPLE	t1	ALL	NULL	NULL	NULL	NULL	1000	5.47	Using where
+1	SIMPLE	t1	ALL	NULL	NULL	NULL	NULL	1000	5.90	Using where
 Warnings:
 Note	1003	select `test`.`t1`.`a` AS `a`,`test`.`t1`.`b` AS `b` from `test`.`t1` USE INDEX () where `test`.`t1`.`b` = 2
 # Now, the equality is used for ref access, while the range condition
@@ -1907,7 +1907,7 @@ test.t1	analyze	status	Engine-independent statistics collected
 test.t1	analyze	status	OK
 EXPLAIN EXTENDED SELECT * from t1 where t1.a >= 81;
 id	select_type	table	type	possible_keys	key	key_len	ref	rows	filtered	Extra
-1	SIMPLE	t1	ALL	NULL	NULL	NULL	NULL	3	66.41	Using where
+1	SIMPLE	t1	ALL	NULL	NULL	NULL	NULL	3	66.67	Using where
 Warnings:
 Note	1003	select `test`.`t1`.`a` AS `a`,`test`.`t1`.`b` AS `b` from `test`.`t1` where `test`.`t1`.`a` >= 81
 SELECT HEX(a), b from t1 where t1.a >= 81;
@@ -1931,7 +1931,7 @@ test.t1	analyze	status	Engine-independent statistics collected
 test.t1	analyze	status	OK
 EXPLAIN EXTENDED SELECT * FROM t1 WHERE a=2;
 id	select_type	table	type	possible_keys	key	key_len	ref	rows	filtered	Extra
-1	SIMPLE	t1	ALL	NULL	NULL	NULL	NULL	5	39.84	Using where
+1	SIMPLE	t1	ALL	NULL	NULL	NULL	NULL	5	40.00	Using where
 Warnings:
 Note	1003	select `test`.`t1`.`a` AS `a` from `test`.`t1` where `test`.`t1`.`a` = 2
 SET optimizer_use_condition_selectivity=3;

mysql-test/main/statistics.result

 set @SINGLE_PREC_TYPE='single_prec_hb';
 set @DOUBLE_PREC_TYPE='double_prec_hb';
-set @DEFAULT_HIST_TYPE=@@histogram_type;
+set @DEFAULT_HIST_TYPE='double_prec_hb';
 drop table if exists t1,t2;
 set @save_use_stat_tables=@@use_stat_tables;
 set @save_histogram_size=@@global.histogram_size;

mysql-test/main/statistics.test

 set @SINGLE_PREC_TYPE='single_prec_hb';
 set @DOUBLE_PREC_TYPE='double_prec_hb';
-set @DEFAULT_HIST_TYPE=@@histogram_type;
+set @DEFAULT_HIST_TYPE='double_prec_hb';
 
 if ($histogram_type_override) {
     eval set @SINGLE_PREC_TYPE=$histogram_type_override;

mysql-test/main/statistics_json.result

@@ -3,7 +3,7 @@
 #
 set @SINGLE_PREC_TYPE='single_prec_hb';
 set @DOUBLE_PREC_TYPE='double_prec_hb';
-set @DEFAULT_HIST_TYPE=@@histogram_type;
+set @DEFAULT_HIST_TYPE='double_prec_hb';
 set @SINGLE_PREC_TYPE='JSON_HB';
 set @DOUBLE_PREC_TYPE='JSON_HB';
 set @DEFAULT_HIST_TYPE='JSON_HB';
@@ -4244,15 +4244,15 @@ test	t1_json	a	a-0	a-9	0.0000	3.0000	1.0000	10	JSON_HB	{
 }
 explain extended select * from t1_json where a between 'a-3a' and 'zzzzzzzzz';
 id	select_type	table	type	possible_keys	key	key_len	ref	rows	filtered	Extra
-1	SIMPLE	t1_json	ALL	NULL	NULL	NULL	NULL	10	58.71	Using where
+1	SIMPLE	t1_json	ALL	NULL	NULL	NULL	NULL	10	68.71	Using where
 Warnings:
 Note	1003	select `test`.`t1_json`.`a` AS `a` from `test`.`t1_json` where `test`.`t1_json`.`a` between 'a-3a' and 'zzzzzzzzz'
 analyze select * from t1_json where a between 'a-3a' and 'zzzzzzzzz';
 id	select_type	table	type	possible_keys	key	key_len	ref	rows	r_rows	filtered	r_filtered	Extra
-1	SIMPLE	t1_json	ALL	NULL	NULL	NULL	NULL	10	10.00	58.71	60.00	Using where
+1	SIMPLE	t1_json	ALL	NULL	NULL	NULL	NULL	10	10.00	68.71	60.00	Using where
 explain extended select * from t1_json where a < 'b-1a';
 id	select_type	table	type	possible_keys	key	key_len	ref	rows	filtered	Extra
-1	SIMPLE	t1_json	ALL	NULL	NULL	NULL	NULL	10	90.00	Using where
+1	SIMPLE	t1_json	ALL	NULL	NULL	NULL	NULL	10	100.00	Using where
 Warnings:
 Note	1003	select `test`.`t1_json`.`a` AS `a` from `test`.`t1_json` where `test`.`t1_json`.`a` < 'b-1a'
 analyze select * from t1_json where a > 'zzzzzzzzz';
@@ -7529,7 +7529,7 @@ test.t1	analyze	status	OK
 analyze
 select c from t1 where c > '1';
 id	select_type	table	type	possible_keys	key	key_len	ref	rows	r_rows	filtered	r_filtered	Extra
-1	SIMPLE	t1	ALL	NULL	NULL	NULL	NULL	16	16.00	75.00	75.00	Using where
+1	SIMPLE	t1	ALL	NULL	NULL	NULL	NULL	16	16.00	80.47	75.00	Using where
 drop table t1;
 #
 # MDEV-26849: JSON Histograms: point selectivity estimates are off for non-existent values

mysql-test/suite/sys_vars/r/histogram_type_basic.result

 SET @start_global_value = @@global.histogram_type;
 SELECT @start_global_value;
 @start_global_value
-DOUBLE_PREC_HB
+JSON_HB
 SET @start_session_value = @@session.histogram_type;
 SELECT @start_session_value;
 @start_session_value
-DOUBLE_PREC_HB
+JSON_HB
 SET @@global.histogram_type = 1;
 SET @@global.histogram_type = DEFAULT;
 SELECT @@global.histogram_type;
 @@global.histogram_type
-DOUBLE_PREC_HB
+JSON_HB
 SET @@global.histogram_type = 0;
 SELECT @@global.histogram_type;
 @@global.histogram_type
@@ -71,9 +71,9 @@ HISTOGRAM_TYPE	DOUBLE_PREC_HB
 SET @@global.histogram_type = @start_global_value;
 SELECT @@global.histogram_type;
 @@global.histogram_type
-DOUBLE_PREC_HB
+JSON_HB
 SET @@session.histogram_type = @start_session_value;
 SELECT @@session.histogram_type;
 @@session.histogram_type
-DOUBLE_PREC_HB
+JSON_HB
 set sql_mode='';

sql/opt_histogram_json.cc

@@ -136,7 +136,7 @@ class Histogram_json_builder : public Histogram_builder
       We may end up producing a histogram with fewer buckets than intended, but
       this is considered tolerable.
     */
-    bucket_capacity= round(rows2double(records) / histogram->get_width() + 0.5);
+    bucket_capacity= (longlong)round(rows2double(records) / histogram->get_width() + 0.5);
     if (bucket_capacity == 0)
       bucket_capacity= 1;
     hist_width= histogram->get_width();

sql/sys_vars.cc

@@ -6499,7 +6499,7 @@ static Sys_var_enum Sys_histogram_type(
        "DOUBLE_PREC_HB - double precision height-balanced, "
        "JSON_HB - height-balanced, stored as JSON.",
        SESSION_VAR(histogram_type), CMD_LINE(REQUIRED_ARG),
-       histogram_types, DEFAULT(1));
+       histogram_types, DEFAULT(2));
 
 static Sys_var_mybool Sys_no_thread_alarm(
        "debug_no_thread_alarm",