MDEV-24487 Error after update to 10.5.8 on CentOS-8: DBD::mysql::st e…

…xecute failed: Unknown MySQL error

The problem happened because the the new client capability flag
CLIENT_EXTENDED_METADATA was not put into the cache entry key.
So results cached by a new client were sent to the old client (and vica versa)
with a mis-matching metadata, which made the client abort the connection on
an unexpected result set metadata packet format.

The problem was caused by the patch for:
  MDEV-17832 Protocol: extensions for Pluggable types and JSON, GEOMETRY
which forgot to adjust the query cache code.

Fix:

- Adding a new member Query_cache_query_flags::client_extended_metadata,
  so only clients with equal CLIENT_EXTENDED_METADATA flag values can
  reuse results.

- Adding a new column CLIENT_EXTENDED_METADATA into
  INFORMATION_SCHEMA.QUERY_CACHE_INFO (privided by the qc_info plugin).

mysql-test/suite/plugins/r/qc_info.result

@@ -27,9 +27,9 @@ set time_zone=@new_time_zone,default_week_format=4,character_set_client='binary'
 select * from t1;
 set time_zone= @time_zone, default_week_format= @default_week_format, character_set_client= @character_set_client,character_set_results= @character_set_results, sql_mode= @sql_mode, div_precision_increment= @div_precision_increment, lc_time_names= @lc_time_names, autocommit= @autocommit, group_concat_max_len= @group_concat_max_len, max_sort_length= @max_sort_length;
 select * from information_schema.query_cache_info;
-STATEMENT_SCHEMA	STATEMENT_TEXT	RESULT_BLOCKS_COUNT	RESULT_BLOCKS_SIZE	RESULT_BLOCKS_SIZE_USED	LIMIT	MAX_SORT_LENGTH	GROUP_CONCAT_MAX_LENGTH	CHARACTER_SET_CLIENT	CHARACTER_SET_RESULT	COLLATION	TIMEZONE	DEFAULT_WEEK_FORMAT	DIV_PRECISION_INCREMENT	SQL_MODE	LC_TIME_NAMES	CLIENT_LONG_FLAG	CLIENT_PROTOCOL_41	PROTOCOL_TYPE	MORE_RESULTS_EXISTS	IN_TRANS	AUTOCOMMIT	PACKET_NUMBER	HITS
-test	select * from t1	1	512	#	-1	1011	513	binary	utf32	utf32_bin	Europe/Moscow	4	7	STRICT_ALL_TABLES	ar_SD	1	1	#	0	0	0	#	0
-test	select * from t1	1	512	#	-1	1024	1048576	latin1	latin1	latin1_swedish_ci	SYSTEM	0	4	STRICT_TRANS_TABLES,ERROR_FOR_DIVISION_BY_ZERO,NO_AUTO_CREATE_USER,NO_ENGINE_SUBSTITUTION	en_US	1	1	#	0	0	1	#	0
+STATEMENT_SCHEMA	STATEMENT_TEXT	RESULT_BLOCKS_COUNT	RESULT_BLOCKS_SIZE	RESULT_BLOCKS_SIZE_USED	LIMIT	MAX_SORT_LENGTH	GROUP_CONCAT_MAX_LENGTH	CHARACTER_SET_CLIENT	CHARACTER_SET_RESULT	COLLATION	TIMEZONE	DEFAULT_WEEK_FORMAT	DIV_PRECISION_INCREMENT	SQL_MODE	LC_TIME_NAMES	CLIENT_LONG_FLAG	CLIENT_PROTOCOL_41	CLIENT_EXTENDED_METADATA	PROTOCOL_TYPE	MORE_RESULTS_EXISTS	IN_TRANS	AUTOCOMMIT	PACKET_NUMBER	HITS
+test	select * from t1	1	512	#	-1	1011	513	binary	utf32	utf32_bin	Europe/Moscow	4	7	STRICT_ALL_TABLES	ar_SD	1	1	1	#	0	0	0	#	0
+test	select * from t1	1	512	#	-1	1024	1048576	latin1	latin1	latin1_swedish_ci	SYSTEM	0	4	STRICT_TRANS_TABLES,ERROR_FOR_DIVISION_BY_ZERO,NO_AUTO_CREATE_USER,NO_ENGINE_SUBSTITUTION	en_US	1	1	1	#	0	0	1	#	0
 reset query cache;
 select * from t1;
 a
@@ -49,7 +49,7 @@ select statement_schema, statement_text, result_blocks_count, result_blocks_size
 statement_schema	statement_text	result_blocks_count	result_blocks_size
 set global query_cache_size = 0;
 select * from information_schema.query_cache_info;
-STATEMENT_SCHEMA	STATEMENT_TEXT	RESULT_BLOCKS_COUNT	RESULT_BLOCKS_SIZE	RESULT_BLOCKS_SIZE_USED	LIMIT	MAX_SORT_LENGTH	GROUP_CONCAT_MAX_LENGTH	CHARACTER_SET_CLIENT	CHARACTER_SET_RESULT	COLLATION	TIMEZONE	DEFAULT_WEEK_FORMAT	DIV_PRECISION_INCREMENT	SQL_MODE	LC_TIME_NAMES	CLIENT_LONG_FLAG	CLIENT_PROTOCOL_41	PROTOCOL_TYPE	MORE_RESULTS_EXISTS	IN_TRANS	AUTOCOMMIT	PACKET_NUMBER	HITS
+STATEMENT_SCHEMA	STATEMENT_TEXT	RESULT_BLOCKS_COUNT	RESULT_BLOCKS_SIZE	RESULT_BLOCKS_SIZE_USED	LIMIT	MAX_SORT_LENGTH	GROUP_CONCAT_MAX_LENGTH	CHARACTER_SET_CLIENT	CHARACTER_SET_RESULT	COLLATION	TIMEZONE	DEFAULT_WEEK_FORMAT	DIV_PRECISION_INCREMENT	SQL_MODE	LC_TIME_NAMES	CLIENT_LONG_FLAG	CLIENT_PROTOCOL_41	CLIENT_EXTENDED_METADATA	PROTOCOL_TYPE	MORE_RESULTS_EXISTS	IN_TRANS	AUTOCOMMIT	PACKET_NUMBER	HITS
 set global query_cache_size= default;
 set global query_cache_type=default;
 show query_cache_info;

mysql-test/suite/plugins/r/qc_info_priv.result

@@ -27,9 +27,9 @@ set time_zone=@new_time_zone,default_week_format=4,character_set_client='binary'
 select * from t1;
 set time_zone= @time_zone, default_week_format= @default_week_format, character_set_client= @character_set_client,character_set_results= @character_set_results, sql_mode= @sql_mode, div_precision_increment= @div_precision_increment, lc_time_names= @lc_time_names, autocommit= @autocommit, group_concat_max_len= @group_concat_max_len, max_sort_length= @max_sort_length;
 select * from information_schema.query_cache_info;
-STATEMENT_SCHEMA	STATEMENT_TEXT	RESULT_BLOCKS_COUNT	RESULT_BLOCKS_SIZE	RESULT_BLOCKS_SIZE_USED	LIMIT	MAX_SORT_LENGTH	GROUP_CONCAT_MAX_LENGTH	CHARACTER_SET_CLIENT	CHARACTER_SET_RESULT	COLLATION	TIMEZONE	DEFAULT_WEEK_FORMAT	DIV_PRECISION_INCREMENT	SQL_MODE	LC_TIME_NAMES	CLIENT_LONG_FLAG	CLIENT_PROTOCOL_41	PROTOCOL_TYPE	MORE_RESULTS_EXISTS	IN_TRANS	AUTOCOMMIT	PACKET_NUMBER	HITS
-test	select * from t1	1	512	#	-1	1011	513	binary	utf32	utf32_bin	Europe/Moscow	4	7	STRICT_ALL_TABLES	ar_SD	1	1	#	0	0	0	#	0
-test	select * from t1	1	512	#	-1	1024	1048576	latin1	latin1	latin1_swedish_ci	SYSTEM	0	4	STRICT_TRANS_TABLES,ERROR_FOR_DIVISION_BY_ZERO,NO_AUTO_CREATE_USER,NO_ENGINE_SUBSTITUTION	en_US	1	1	#	0	0	1	#	0
+STATEMENT_SCHEMA	STATEMENT_TEXT	RESULT_BLOCKS_COUNT	RESULT_BLOCKS_SIZE	RESULT_BLOCKS_SIZE_USED	LIMIT	MAX_SORT_LENGTH	GROUP_CONCAT_MAX_LENGTH	CHARACTER_SET_CLIENT	CHARACTER_SET_RESULT	COLLATION	TIMEZONE	DEFAULT_WEEK_FORMAT	DIV_PRECISION_INCREMENT	SQL_MODE	LC_TIME_NAMES	CLIENT_LONG_FLAG	CLIENT_PROTOCOL_41	CLIENT_EXTENDED_METADATA	PROTOCOL_TYPE	MORE_RESULTS_EXISTS	IN_TRANS	AUTOCOMMIT	PACKET_NUMBER	HITS
+test	select * from t1	1	512	#	-1	1011	513	binary	utf32	utf32_bin	Europe/Moscow	4	7	STRICT_ALL_TABLES	ar_SD	1	1	1	#	0	0	0	#	0
+test	select * from t1	1	512	#	-1	1024	1048576	latin1	latin1	latin1_swedish_ci	SYSTEM	0	4	STRICT_TRANS_TABLES,ERROR_FOR_DIVISION_BY_ZERO,NO_AUTO_CREATE_USER,NO_ENGINE_SUBSTITUTION	en_US	1	1	1	#	0	0	1	#	0
 create user mysqltest;
 connect  conn1,localhost,mysqltest,,;
 connection conn1;

mysql-test/suite/plugins/t/qc_info_init.inc

@@ -30,5 +30,5 @@ select * from t1;
 set time_zone= @time_zone, default_week_format= @default_week_format, character_set_client= @character_set_client,character_set_results= @character_set_results, sql_mode= @sql_mode, div_precision_increment= @div_precision_increment, lc_time_names= @lc_time_names, autocommit= @autocommit, group_concat_max_len= @group_concat_max_len, max_sort_length= @max_sort_length;
 
 --sorted_result
---replace_column 5 # 19 # 23 #
+--replace_column 5 # 20 # 24 #
 select * from information_schema.query_cache_info;

plugin/qc_info/qc_info.cc

@@ -72,12 +72,13 @@ bool schema_table_store_record(THD *thd, TABLE *table);
 
 #define COLUMN_CLIENT_LONG_FLAG 16
 #define COLUMN_CLIENT_PROTOCOL_41 17
-#define COLUMN_PROTOCOL_TYPE 18
-#define COLUMN_MORE_RESULTS_EXISTS 19
-#define COLUMN_IN_TRANS 20
-#define COLUMN_AUTOCOMMIT 21
-#define COLUMN_PKT_NR 22
-#define COLUMN_HITS 23
+#define COLUMN_CLIENT_EXTENDED_METADATA 18
+#define COLUMN_PROTOCOL_TYPE 19
+#define COLUMN_MORE_RESULTS_EXISTS 20
+#define COLUMN_IN_TRANS 21
+#define COLUMN_AUTOCOMMIT 22
+#define COLUMN_PKT_NR 23
+#define COLUMN_HITS 24
 
 
 namespace Show {
@@ -103,6 +104,7 @@ static ST_FIELD_INFO qc_info_fields[]=
   Column("LC_TIME_NAMES",         Varchar(100),                       NOT_NULL),
   Column("CLIENT_LONG_FLAG",      STiny(MY_INT32_NUM_DECIMAL_DIGITS), NOT_NULL),
   Column("CLIENT_PROTOCOL_41",    STiny(MY_INT32_NUM_DECIMAL_DIGITS), NOT_NULL),
+  Column("CLIENT_EXTENDED_METADATA",STiny(MY_INT32_NUM_DECIMAL_DIGITS), NOT_NULL),
   Column("PROTOCOL_TYPE",         STiny(MY_INT32_NUM_DECIMAL_DIGITS), NOT_NULL),
   Column("MORE_RESULTS_EXISTS",   STiny(MY_INT32_NUM_DECIMAL_DIGITS), NOT_NULL),
   Column("IN_TRANS",              STiny(MY_INT32_NUM_DECIMAL_DIGITS), NOT_NULL),
@@ -218,6 +220,8 @@ static int qc_info_fill_table(THD *thd, TABLE_LIST *tables,
 
     table->field[COLUMN_CLIENT_LONG_FLAG]->store(flags.client_long_flag, 0);
     table->field[COLUMN_CLIENT_PROTOCOL_41]->store(flags.client_protocol_41, 0);
+    table->field[COLUMN_CLIENT_EXTENDED_METADATA]->
+      store(flags.client_extended_metadata, 0);
     table->field[COLUMN_PROTOCOL_TYPE]->store(flags.protocol_type, 0);
     table->field[COLUMN_MORE_RESULTS_EXISTS]->store(flags.more_results_exists, 0);
     table->field[COLUMN_IN_TRANS]->store(flags.in_trans, 0);

sql/sql_cache.cc

@@ -1415,6 +1415,8 @@ void Query_cache::store_query(THD *thd, TABLE_LIST *tables_used)
     flags.client_long_flag= MY_TEST(thd->client_capabilities & CLIENT_LONG_FLAG);
     flags.client_protocol_41= MY_TEST(thd->client_capabilities &
                                       CLIENT_PROTOCOL_41);
+    flags.client_extended_metadata= MY_TEST(thd->client_capabilities &
+                                            MARIADB_CLIENT_EXTENDED_METADATA);
     flags.client_depr_eof= MY_TEST(thd->client_capabilities &
                                       CLIENT_DEPRECATE_EOF);
     /*
@@ -1447,12 +1449,13 @@ void Query_cache::store_query(THD *thd, TABLE_LIST *tables_used)
     flags.div_precision_increment= thd->variables.div_precincrement;
     flags.default_week_format= thd->variables.default_week_format;
     DBUG_PRINT("qcache", ("\
-long %d, 4.1: %d, eof: %d, bin_proto: %d, more results %d, pkt_nr: %d, \
+long %d, 4.1: %d, ex metadata: %d, eof: %d, bin_proto: %d, more results %d, pkt_nr: %d, \
 CS client: %u, CS result: %u, CS conn: %u, limit: %llu, TZ: %p, \
 sql mode: 0x%llx, sort len: %llu, concat len: %u, div_precision: %zu, \
 def_week_frmt: %zu, in_trans: %d, autocommit: %d",
                           (int)flags.client_long_flag,
                           (int)flags.client_protocol_41,
+                          (int)flags.client_extended_metadata,
                           (int)flags.client_depr_eof,
                           (int)flags.protocol_type,
                           (int)flags.more_results_exists,
@@ -1924,6 +1927,8 @@ Query_cache::send_result_to_client(THD *thd, char *org_sql, uint query_length)
   flags.client_long_flag= MY_TEST(thd->client_capabilities & CLIENT_LONG_FLAG);
   flags.client_protocol_41= MY_TEST(thd->client_capabilities &
                                     CLIENT_PROTOCOL_41);
+  flags.client_extended_metadata= MY_TEST(thd->client_capabilities &
+                                          MARIADB_CLIENT_EXTENDED_METADATA);
   flags.client_depr_eof= MY_TEST(thd->client_capabilities &
                                     CLIENT_DEPRECATE_EOF);
   flags.protocol_type= (unsigned int) thd->protocol->type();
@@ -1947,12 +1952,13 @@ Query_cache::send_result_to_client(THD *thd, char *org_sql, uint query_length)
   flags.default_week_format= thd->variables.default_week_format;
   flags.lc_time_names= thd->variables.lc_time_names;
   DBUG_PRINT("qcache", ("\
-long %d, 4.1: %d, eof: %d, bin_proto: %d, more results %d, pkt_nr: %d, \
+long %d, 4.1: %d, ex metadata: %d, eof: %d, bin_proto: %d, more results %d, pkt_nr: %d, \
 CS client: %u, CS result: %u, CS conn: %u, limit: %llu, TZ: %p, \
 sql mode: 0x%llx, sort len: %llu, concat len: %u, div_precision: %zu, \
 def_week_frmt: %zu, in_trans: %d, autocommit: %d",
                           (int)flags.client_long_flag,
                           (int)flags.client_protocol_41,
+                          (int)flags.client_extended_metadata,
                           (int)flags.client_depr_eof,
                           (int)flags.protocol_type,
                           (int)flags.more_results_exists,

sql/sql_cache.h

@@ -549,6 +549,7 @@ struct Query_cache_query_flags
 {
   unsigned int client_long_flag:1;
   unsigned int client_protocol_41:1;
+  unsigned int client_extended_metadata:1;
   unsigned int client_depr_eof:1;
   unsigned int protocol_type:2;
   unsigned int more_results_exists:1;