MDEV-39791: Handle count aggregate optimization for replay purpose

mysql-test/include/get_rec_idx_ranges_from_opt_ctx.inc

@@ -25,3 +25,9 @@ select *from json_table(
                       num_rows int path '$.num_rows',
                       max_index_blocks int path '$.max_index_blocks',
                       max_row_blocks int path '$.max_row_blocks')) as jt;
+set @table_contexts=
+    (select JSON_DETAILED(JSON_EXTRACT(@opt_context, '$**.list_contexts')));
+select *from json_table(
+    @table_contexts,
+    '$[*][*]' columns(table_name text path '$.name',
+                      count_agg int path '$.count_agg')) as jt;

mysql-test/include/opt_context_schema.inc

@@ -187,6 +187,9 @@ let $opt_context_schema=
                 "copy_cost"
               ]
             }
+          },
+          "count_agg": {
+            "type": "number"
           }
         },
         "required": [

mysql-test/main/opt_context_load_stats_basic.result

@@ -68,6 +68,14 @@ index_name	ranges	num_rows	max_index_blocks	max_row_blocks
 t1_idx_a	["(NULL) < (a) < (3)"]	12	1	1
 t1_idx_b	["(6) < (b)"]	2	1	1
 t1_idx_ab	["(NULL) < (a) < (3)"]	12	1	1
+set @table_contexts=
+(select JSON_DETAILED(JSON_EXTRACT(@opt_context, '$**.list_contexts')));
+select *from json_table(
+@table_contexts,
+'$[*][*]' columns(table_name text path '$.name',
+count_agg int path '$.count_agg')) as jt;
+table_name	count_agg
+db1.t1	NULL
 set @saved_opt_context_1=@opt_context;
 set @saved_records_1=@records;
 set @saved_indexes_1=@indexes;
@@ -355,11 +363,6 @@ select * from t1 where a > 10;
 a	b
 Warnings:
 Warning	4253	Failed to parse saved optimizer context: "file_stat_records" element not present at offset 1380.
-set @opt_context=json_remove(@saved_opt_context_1, '$.list_contexts[0].file_stat_records');
-select * from t1 where a > 10;
-a	b
-Warnings:
-Warning	4253	Failed to parse saved optimizer context: "file_stat_records" element not present at offset 1380.
 set @opt_context=json_remove(@saved_opt_context_1, '$.list_contexts[0].indexes[0].index_name');
 select * from t1 where a > 10;
 a	b
@@ -488,4 +491,37 @@ a	b
 Warnings:
 Warning	4253	Failed to parse saved optimizer context: "copy_cost" element not present at offset 514.
 drop table t1;
+set optimizer_replay_context="";
+create table t1 (a int primary key, b int not null, c varchar(10));
+insert into t1 select seq, seq%5, concat('a-', seq) from seq_1_to_10;
+set optimizer_record_context=1;
+explain
+select count(a), count(b), count(c) from t1;
+id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
+1	SIMPLE	t1	ALL	NULL	NULL	NULL	NULL	10	
+set @opt_context=
+(select REGEXP_SUBSTR(
+context,
+'(?<=set @opt_context=\')([\n\r].*)*(?=\'\;#opt_context_ends)')
+from information_schema.optimizer_context);
+set @saved_opt_context_1= @opt_context;
+set optimizer_replay_context=@opt_context_var_name;
+set @opt_context=json_remove(@saved_opt_context_1, '$.list_contexts[0].count_agg');
+explain
+select count(a) from t1;
+id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
+1	SIMPLE	NULL	NULL	NULL	NULL	NULL	NULL	NULL	Select tables optimized away
+Warnings:
+Warning	4254	Failed to match the stats from replay context with the optimizer stats: db1.t1 with count_agg:  doesn't exist in list_contexts
+explain
+select count(b) from t1;
+id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
+1	SIMPLE	NULL	NULL	NULL	NULL	NULL	NULL	NULL	Select tables optimized away
+Warnings:
+Warning	4254	Failed to match the stats from replay context with the optimizer stats: db1.t1 with count_agg:  doesn't exist in list_contexts
+explain
+select count(c) from t1;
+id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
+1	SIMPLE	t1	ALL	NULL	NULL	NULL	NULL	10	
+drop table t1;
 drop database db1;

mysql-test/main/opt_context_load_stats_basic.test

@@ -226,9 +226,6 @@ select * from t1 where a > 10;
 set @opt_context=json_remove(@saved_opt_context_1, '$.list_contexts[0].file_stat_records');
 select * from t1 where a > 10;
 
-set @opt_context=json_remove(@saved_opt_context_1, '$.list_contexts[0].file_stat_records');
-select * from t1 where a > 10;
-
 set @opt_context=json_remove(@saved_opt_context_1, '$.list_contexts[0].indexes[0].index_name');
 select * from t1 where a > 10;
 
@@ -300,5 +297,30 @@ select * from t1 where a > 10;
 set @opt_context=json_remove(@saved_opt_context_1, '$.list_contexts[0].list_index_read_costs[0].copy_cost');
 select * from t1 where a > 10;
 
+drop table t1;
+set optimizer_replay_context="";
+
+create table t1 (a int primary key, b int not null, c varchar(10));
+insert into t1 select seq, seq%5, concat('a-', seq) from seq_1_to_10;
+
+set optimizer_record_context=1;
+
+explain
+select count(a), count(b), count(c) from t1;
+
+--source include/get_opt_context.inc
+set @saved_opt_context_1= @opt_context;
+
+set optimizer_replay_context=@opt_context_var_name;
+set @opt_context=json_remove(@saved_opt_context_1, '$.list_contexts[0].count_agg');
+explain
+select count(a) from t1;
+
+explain
+select count(b) from t1;
+
+explain
+select count(c) from t1;
+
 drop table t1;
 drop database db1;

mysql-test/main/opt_context_replay_basic.result

@@ -124,7 +124,7 @@ SET optimizer_where_cost=0.032000;
 
 SET sql_mode='STRICT_TRANS_TABLES,ERROR_FOR_DIVISION_BY_ZERO,NO_AUTO_CREATE_USER,NO_ENGINE_SUBSTITUTION';
 
-SET timestamp=1780212030.000000;
+SET timestamp=1780203030.000000;
 
 
 select count(*) from t1;
@@ -205,7 +205,7 @@ SET optimizer_trace_max_mem_size=1048576;
 SET optimizer_use_condition_selectivity=4;
 SET optimizer_where_cost=0.032000;
 SET sql_mode='STRICT_TRANS_TABLES,ERROR_FOR_DIVISION_BY_ZERO,NO_AUTO_CREATE_USER,NO_ENGINE_SUBSTITUTION';
-SET timestamp=1780212030.000000;
+SET timestamp=1780203030.000000;
 CREATE DATABASE IF NOT EXISTS db1;
 Warnings:
 Note	1007	Can't create database 'db1'; database exists