Rename histogram_type=JSON to JSON_HB

mysql-test/main/statistics_json.test

@@ -2,7 +2,7 @@
 --echo # Test that we can store JSON arrays in histogram field mysql.column_stats when histogram_type=JSON
 --echo #
 
-let $histogram_type_override='JSON';
+let $histogram_type_override='JSON_HB';
 --source statistics.test
 
 --source include/have_stat_tables.inc
@@ -27,7 +27,7 @@ select hex(histogram) from mysql.column_stats where table_name='t1_bin';
 explain extended select * from t1_bin where a between 'a-3a' and 'zzzzzzzzz';
 analyze select * from t1_bin where a between 'a-3a' and 'zzzzzzzzz';
 
-set histogram_type=json;
+set histogram_type=json_hb;
 create table t1_json (a varchar(255));
 insert into t1_json select concat('a-', a) from ten;
 analyze table t1_json persistent for all;
@@ -51,7 +51,7 @@ create table users (
 set histogram_size=50;
 insert into users select 'Moscow' from seq_1_to_99;
 insert into users select 'Helsinki' from seq_1_to_2;
-set histogram_type=json;
+set histogram_type=json_hb;
 analyze table users persistent for all;
 explain extended select * from users where city = 'Moscow';
 analyze select * from users where city = 'Moscow';
@@ -76,7 +76,7 @@ use world;
 --enable_result_log
 --enable_query_log
 
-set histogram_type='JSON';
+set histogram_type='JSON_HB';
 set histogram_size=50;
 --disable_result_log
 ANALYZE TABLE Country, City, CountryLanguage persistent for all;
@@ -91,4 +91,4 @@ analyze select * from Country where 'Code' < 'BBC';
 set histogram_type=@save_histogram_type;
 set histogram_size=@save_histogram_size;
 
-DROP SCHEMA world;
\ No newline at end of file
+DROP SCHEMA world;

mysql-test/main/system_mysql_db.result

@@ -234,7 +234,7 @@ column_stats	CREATE TABLE `column_stats` (
   `avg_length` decimal(12,4) DEFAULT NULL,
   `avg_frequency` decimal(12,4) DEFAULT NULL,
   `hist_size` tinyint(3) unsigned DEFAULT NULL,
-  `hist_type` enum('SINGLE_PREC_HB','DOUBLE_PREC_HB','JSON') COLLATE utf8mb3_bin DEFAULT NULL,
+  `hist_type` enum('SINGLE_PREC_HB','DOUBLE_PREC_HB','JSON_HB') COLLATE utf8mb3_bin DEFAULT NULL,
   `histogram` blob DEFAULT NULL,
   PRIMARY KEY (`db_name`,`table_name`,`column_name`)
 ) ENGINE=Aria DEFAULT CHARSET=utf8mb3 COLLATE=utf8mb3_bin PAGE_CHECKSUM=1 TRANSACTIONAL=0 COMMENT='Statistics on Columns'

mysql-test/main/system_mysql_db_fix40123.result

@@ -272,7 +272,7 @@ column_stats	CREATE TABLE `column_stats` (
   `avg_length` decimal(12,4) DEFAULT NULL,
   `avg_frequency` decimal(12,4) DEFAULT NULL,
   `hist_size` tinyint(3) unsigned DEFAULT NULL,
-  `hist_type` enum('SINGLE_PREC_HB','DOUBLE_PREC_HB','JSON') COLLATE utf8mb3_bin DEFAULT NULL,
+  `hist_type` enum('SINGLE_PREC_HB','DOUBLE_PREC_HB','JSON_HB') COLLATE utf8mb3_bin DEFAULT NULL,
   `histogram` blob DEFAULT NULL,
   PRIMARY KEY (`db_name`,`table_name`,`column_name`)
 ) ENGINE=Aria DEFAULT CHARSET=utf8mb3 COLLATE=utf8mb3_bin PAGE_CHECKSUM=1 TRANSACTIONAL=0 COMMENT='Statistics on Columns'

mysql-test/main/system_mysql_db_fix50030.result

@@ -276,7 +276,7 @@ column_stats	CREATE TABLE `column_stats` (
   `avg_length` decimal(12,4) DEFAULT NULL,
   `avg_frequency` decimal(12,4) DEFAULT NULL,
   `hist_size` tinyint(3) unsigned DEFAULT NULL,
-  `hist_type` enum('SINGLE_PREC_HB','DOUBLE_PREC_HB','JSON') COLLATE utf8mb3_bin DEFAULT NULL,
+  `hist_type` enum('SINGLE_PREC_HB','DOUBLE_PREC_HB','JSON_HB') COLLATE utf8mb3_bin DEFAULT NULL,
   `histogram` blob DEFAULT NULL,
   PRIMARY KEY (`db_name`,`table_name`,`column_name`)
 ) ENGINE=Aria DEFAULT CHARSET=utf8mb3 COLLATE=utf8mb3_bin PAGE_CHECKSUM=1 TRANSACTIONAL=0 COMMENT='Statistics on Columns'

mysql-test/main/system_mysql_db_fix50117.result

@@ -256,7 +256,7 @@ column_stats	CREATE TABLE `column_stats` (
   `avg_length` decimal(12,4) DEFAULT NULL,
   `avg_frequency` decimal(12,4) DEFAULT NULL,
   `hist_size` tinyint(3) unsigned DEFAULT NULL,
-  `hist_type` enum('SINGLE_PREC_HB','DOUBLE_PREC_HB','JSON') COLLATE utf8mb3_bin DEFAULT NULL,
+  `hist_type` enum('SINGLE_PREC_HB','DOUBLE_PREC_HB','JSON_HB') COLLATE utf8mb3_bin DEFAULT NULL,
   `histogram` blob DEFAULT NULL,
   PRIMARY KEY (`db_name`,`table_name`,`column_name`)
 ) ENGINE=Aria DEFAULT CHARSET=utf8mb3 COLLATE=utf8mb3_bin PAGE_CHECKSUM=1 TRANSACTIONAL=0 COMMENT='Statistics on Columns'

mysql-test/suite/funcs_1/r/is_columns_mysql.result

@@ -13,9 +13,9 @@ def	mysql	column_stats	avg_frequency	8	NULL	YES	decimal	NULL	NULL	12	4	NULL	NULL
 def	mysql	column_stats	avg_length	7	NULL	YES	decimal	NULL	NULL	12	4	NULL	NULL	NULL	decimal(12,4)			select,insert,update,references		NEVER	NULL
 def	mysql	column_stats	column_name	3	NULL	NO	varchar	64	192	NULL	NULL	NULL	utf8mb3	utf8mb3_bin	varchar(64)	PRI		select,insert,update,references		NEVER	NULL
 def	mysql	column_stats	db_name	1	NULL	NO	varchar	64	192	NULL	NULL	NULL	utf8mb3	utf8mb3_bin	varchar(64)	PRI		select,insert,update,references		NEVER	NULL
-def	mysql	column_stats	histogram	11	NULL	YES	varbinary	255	255	NULL	NULL	NULL	NULL	NULL	varbinary(255)			select,insert,update,references		NEVER	NULL
+def	mysql	column_stats	histogram	11	NULL	YES	blob	65535	65535	NULL	NULL	NULL	NULL	NULL	blob			select,insert,update,references		NEVER	NULL
 def	mysql	column_stats	hist_size	9	NULL	YES	tinyint	NULL	NULL	3	0	NULL	NULL	NULL	tinyint(3) unsigned			select,insert,update,references		NEVER	NULL
-def	mysql	column_stats	hist_type	10	NULL	YES	enum	14	42	NULL	NULL	NULL	utf8mb3	utf8mb3_bin	enum('SINGLE_PREC_HB','DOUBLE_PREC_HB')			select,insert,update,references		NEVER	NULL
+def	mysql	column_stats	hist_type	10	NULL	YES	enum	14	42	NULL	NULL	NULL	utf8mb3	utf8mb3_bin	enum('SINGLE_PREC_HB','DOUBLE_PREC_HB','JSON_HB')			select,insert,update,references		NEVER	NULL
 def	mysql	column_stats	max_value	5	NULL	YES	varbinary	255	255	NULL	NULL	NULL	NULL	NULL	varbinary(255)			select,insert,update,references		NEVER	NULL
 def	mysql	column_stats	min_value	4	NULL	YES	varbinary	255	255	NULL	NULL	NULL	NULL	NULL	varbinary(255)			select,insert,update,references		NEVER	NULL
 def	mysql	column_stats	nulls_ratio	6	NULL	YES	decimal	NULL	NULL	12	4	NULL	NULL	NULL	decimal(12,4)			select,insert,update,references		NEVER	NULL
@@ -345,8 +345,8 @@ NULL	mysql	column_stats	nulls_ratio	decimal	NULL	NULL	NULL	NULL	decimal(12,4)
 NULL	mysql	column_stats	avg_length	decimal	NULL	NULL	NULL	NULL	decimal(12,4)
 NULL	mysql	column_stats	avg_frequency	decimal	NULL	NULL	NULL	NULL	decimal(12,4)
 NULL	mysql	column_stats	hist_size	tinyint	NULL	NULL	NULL	NULL	tinyint(3) unsigned
-3.0000	mysql	column_stats	hist_type	enum	14	42	utf8mb3	utf8mb3_bin	enum('SINGLE_PREC_HB','DOUBLE_PREC_HB')
-1.0000	mysql	column_stats	histogram	varbinary	255	255	NULL	NULL	varbinary(255)
+3.0000	mysql	column_stats	hist_type	enum	14	42	utf8mb3	utf8mb3_bin	enum('SINGLE_PREC_HB','DOUBLE_PREC_HB','JSON_HB')
+1.0000	mysql	column_stats	histogram	blob	65535	65535	NULL	NULL	blob
 3.0000	mysql	db	Host	char	255	765	utf8mb3	utf8mb3_bin	char(255)
 3.0000	mysql	db	Db	char	64	192	utf8mb3	utf8mb3_bin	char(64)
 3.0000	mysql	db	User	char	128	384	utf8mb3	utf8mb3_bin	char(128)

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

@@ -1309,7 +1309,7 @@ VARIABLE_COMMENT	Specifies type of the histograms created by ANALYZE. Possible v
 NUMERIC_MIN_VALUE	NULL
 NUMERIC_MAX_VALUE	NULL
 NUMERIC_BLOCK_SIZE	NULL
-ENUM_VALUE_LIST	SINGLE_PREC_HB,DOUBLE_PREC_HB
+ENUM_VALUE_LIST	SINGLE_PREC_HB,DOUBLE_PREC_HB,JSON_HB
 READ_ONLY	NO
 COMMAND_LINE_ARGUMENT	REQUIRED
 VARIABLE_NAME	HOSTNAME

scripts/mysql_system_tables.sql

@@ -314,7 +314,7 @@ DROP TABLE tmp_proxies_priv;
 
 CREATE TABLE IF NOT EXISTS table_stats (db_name varchar(64) NOT NULL, table_name varchar(64) NOT NULL, cardinality bigint(21) unsigned DEFAULT NULL, PRIMARY KEY (db_name,table_name) ) engine=Aria transactional=0 CHARACTER SET utf8 COLLATE utf8_bin comment='Statistics on Tables';
 
-CREATE TABLE IF NOT EXISTS column_stats (db_name varchar(64) NOT NULL, table_name varchar(64) NOT NULL, column_name varchar(64) NOT NULL, min_value varbinary(255) DEFAULT NULL, max_value varbinary(255) DEFAULT NULL, nulls_ratio decimal(12,4) DEFAULT NULL, avg_length decimal(12,4) DEFAULT NULL, avg_frequency decimal(12,4) DEFAULT NULL, hist_size tinyint unsigned, hist_type enum('SINGLE_PREC_HB','DOUBLE_PREC_HB','JSON'), histogram blob, PRIMARY KEY (db_name,table_name,column_name) ) engine=Aria transactional=0 CHARACTER SET utf8 COLLATE utf8_bin comment='Statistics on Columns';
+CREATE TABLE IF NOT EXISTS column_stats (db_name varchar(64) NOT NULL, table_name varchar(64) NOT NULL, column_name varchar(64) NOT NULL, min_value varbinary(255) DEFAULT NULL, max_value varbinary(255) DEFAULT NULL, nulls_ratio decimal(12,4) DEFAULT NULL, avg_length decimal(12,4) DEFAULT NULL, avg_frequency decimal(12,4) DEFAULT NULL, hist_size tinyint unsigned, hist_type enum('SINGLE_PREC_HB','DOUBLE_PREC_HB','JSON_HB'), histogram blob, PRIMARY KEY (db_name,table_name,column_name) ) engine=Aria transactional=0 CHARACTER SET utf8 COLLATE utf8_bin comment='Statistics on Columns';
 
 CREATE TABLE IF NOT EXISTS index_stats (db_name varchar(64) NOT NULL, table_name varchar(64) NOT NULL, index_name varchar(64) NOT NULL, prefix_arity int(11) unsigned NOT NULL, avg_frequency decimal(12,4) DEFAULT NULL, PRIMARY KEY (db_name,table_name,index_name,prefix_arity) ) engine=Aria transactional=0 CHARACTER SET utf8 COLLATE utf8_bin comment='Statistics on Indexes';
 

sql/item_strfunc.cc

@@ -503,7 +503,7 @@ String *Item_func_from_base64::val_str(String *str)
 
 
 const char *histogram_types[] =
-    {"SINGLE_PREC_HB", "DOUBLE_PREC_HB", "JSON", 0};
+    {"SINGLE_PREC_HB", "DOUBLE_PREC_HB", "JSON_HB", 0};
 static TYPELIB histogram_types_typelib=
   { array_elements(histogram_types),
     "histogram_types",
@@ -533,6 +533,13 @@ String *Item_func_decode_histogram::val_str(String *str)
     null_value= 1;
     return 0;
   }
+
+  if (type == JSON_HB)
+  {
+    // It's a JSON histogram. Return it as-is.
+    return res;
+  }
+
   if (type == DOUBLE_PREC_HB && res->length() % 2 != 0)
     res->length(res->length() - 1); // one byte is unused
 
@@ -541,10 +548,6 @@ String *Item_func_decode_histogram::val_str(String *str)
   str->length(0);
   char numbuf[32];
   const uchar *p= (uchar*)res->c_ptr_safe();
-  if (type == JSON)
-  {
-    return res;
-  }
   for (i= 0; i < res->length(); i++)
   {
     double val;

sql/sql_statistics.cc

@@ -193,7 +193,7 @@ TABLE_FIELD_TYPE column_stat_fields[COLUMN_STAT_N_FIELDS] =
   },
   {
     { STRING_WITH_LEN("hist_type") },
-    { STRING_WITH_LEN("enum('SINGLE_PREC_HB','DOUBLE_PREC_HB','JSON')") },
+    { STRING_WITH_LEN("enum('SINGLE_PREC_HB','DOUBLE_PREC_HB','JSON_HB')") },
     { STRING_WITH_LEN("utf8mb3") }
   },
   {
@@ -1234,7 +1234,7 @@ class Column_stat: public Stat_table
       case DOUBLE_PREC_HB:
         hist = new (mem_root) Histogram_binary();
         break;
-      case JSON:
+      case JSON_HB:
         hist = new (mem_root) Histogram_json();
         break;
       default:
@@ -2046,7 +2046,7 @@ class Histogram_builder_json : public Histogram_builder
 Histogram_base *create_histogram(Histogram_type hist_type)
 {
   // assumes the caller already checked for invalid histograms
-  if (hist_type == JSON)
+  if (hist_type == JSON_HB)
     return new Histogram_json;
   else
     return new Histogram_binary;
@@ -2207,7 +2207,7 @@ class Count_distinct_field: public Sql_alloc
   */
   void walk_tree_with_histogram(ha_rows rows)
   {
-    if (table_field->collected_stats->histogram_->get_type() == JSON)
+    if (table_field->collected_stats->histogram_->get_type() == JSON_HB)
     {
       Histogram_builder_json hist_builder(table_field, tree_key_length, rows);
       tree->walk(table_field->table, json_histogram_build_walk,
@@ -2915,7 +2915,7 @@ Histogram_base * get_histogram_by_type(MEM_ROOT *mem_root, Histogram_type hist_t
   case SINGLE_PREC_HB:
   case DOUBLE_PREC_HB:
     return new Histogram_binary();
-  case JSON:
+  case JSON_HB:
     return new Histogram_json();
   default:
     DBUG_ASSERT(0);

sql/sql_statistics.h

@@ -44,7 +44,7 @@ enum enum_histogram_type
 {
   SINGLE_PREC_HB,
   DOUBLE_PREC_HB,
-  JSON,
+  JSON_HB,
   INVALID_HISTOGRAM
 } Histogram_type;
 
@@ -374,7 +374,7 @@ class Histogram_json : public Histogram_base
 
   Histogram_type get_type() override
   {
-    return JSON;
+    return JSON_HB;
   }
 
   void set_size (ulonglong sz) override {size = (uint8) sz; }