Merge 10.4 into 10.5

libmariadb @ 62427520

-Subproject commit 0cdc1656a70c52103b4329debf9ed02ccacfb3c2
+Subproject commit 62427520a5ba20e42fe51f5045062a7a9cadb466

mysql-test/main/innodb_ext_key,off.rdiff

+--- innodb_ext_key.result
++++ innodb_ext_key,off.result
 @@ -9,7 +9,7 @@
  explain
  select count(*) from lineitem where l_orderkey=130 and l_shipdate='1992-07-01';
  id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
 -1	SIMPLE	lineitem	ref	PRIMARY,i_l_shipdate,i_l_orderkey,i_l_orderkey_quantity	i_l_shipdate	8	const,const	1	Using index
-+1	SIMPLE	lineitem	ref	PRIMARY,i_l_shipdate,i_l_orderkey,i_l_orderkey_quantity	PRIMARY	4	const	5	Using where
++1	SIMPLE	lineitem	ref	PRIMARY,i_l_shipdate,i_l_orderkey,i_l_orderkey_quantity	i_l_shipdate	4	const	6	Using where; Using index
  flush status;
  select count(*) from lineitem where l_orderkey=130 and l_shipdate='1992-07-01';
  count(*)
@@ -12,7 +14,7 @@
  Handler_read_key	1
  Handler_read_last	0
 -Handler_read_next	1
-+Handler_read_next	5
++Handler_read_next	6
  Handler_read_prev	0
  Handler_read_retry	0
  Handler_read_rnd	0
@@ -93,7 +95,7 @@
  where l_shipdate='1992-07-01' and l_orderkey=130;
  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
-+1	SIMPLE	lineitem	ref	PRIMARY,i_l_shipdate,i_l_orderkey,i_l_orderkey_quantity	PRIMARY	4	const	5	Using where
++1	SIMPLE	lineitem	ref	PRIMARY,i_l_shipdate,i_l_orderkey,i_l_orderkey_quantity	i_l_shipdate	4	const	6	Using where; Using index
  flush status;
  select max(l_linenumber) from lineitem 
  where l_shipdate='1992-07-01' and l_orderkey=130;
@@ -102,7 +104,7 @@
  Handler_read_key	1
  Handler_read_last	0
 -Handler_read_next	0
-+Handler_read_next	5
++Handler_read_next	6
  Handler_read_prev	0
  Handler_read_retry	0
  Handler_read_rnd	0

mysql-test/main/innodb_ext_key.result

@@ -26,12 +26,12 @@ Handler_read_rnd	0
 Handler_read_rnd_deleted	0
 Handler_read_rnd_next	0
 explain
-select count(*) from lineitem
+select count(*) from lineitem use index(primary)
 where l_orderkey=130 and l_linenumber=2 and l_shipdate='1992-07-01';
 id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
-1	SIMPLE	lineitem	const	PRIMARY,i_l_shipdate,i_l_orderkey,i_l_orderkey_quantity	PRIMARY	8	const,const	1	
+1	SIMPLE	lineitem	const	PRIMARY	PRIMARY	8	const,const	1	
 flush status;
-select count(*) from lineitem 
+select count(*) from lineitem use index(primary)
 where l_orderkey=130 and l_linenumber=2 and l_shipdate='1992-07-01';
 count(*)
 1

mysql-test/main/innodb_ext_key.test

@@ -17,6 +17,7 @@ use dbt3_s001;
 --disable_result_log
 --disable_warnings
 --source include/dbt3_s001.inc
+ANALYZE TABLE lineitem PERSISTENT FOR COLUMNS() INDEXES();
 --enable_warnings
 --enable_result_log
 --enable_query_log
@@ -28,10 +29,10 @@ select count(*) from lineitem where l_orderkey=130 and l_shipdate='1992-07-01';
 show status like 'handler_read%';
 
 explain
-select count(*) from lineitem
+select count(*) from lineitem use index(primary)
   where l_orderkey=130 and l_linenumber=2 and l_shipdate='1992-07-01';
 flush status;
-select count(*) from lineitem 
+select count(*) from lineitem use index(primary)
   where l_orderkey=130 and l_linenumber=2 and l_shipdate='1992-07-01';
 show status like 'handler_read%';
 

sql/sql_string.h

@@ -314,7 +314,8 @@ class Static_binary_string : public Sql_alloc
   }
   void q_append(const char *data, size_t data_len)
   {
-    memcpy(Ptr + str_length, data, data_len);
+    if (data_len)
+      memcpy(Ptr + str_length, data, data_len);
     DBUG_ASSERT(str_length <= UINT_MAX32 - data_len);
     str_length += (uint)data_len;
   }