diff --git a/mysql-test/r/union.result b/mysql-test/r/union.result
index 05870d23ed6..fd01133afbc 100644
--- a/mysql-test/r/union.result
+++ b/mysql-test/r/union.result
@@ -1283,10 +1283,39 @@ b
 create table t3 SELECT left(a,100000000) FROM t1 UNION  SELECT b FROM t2;
 show create table t3;
 Table	Create Table
+t3	CREATE TABLE `t3` (
+  `left(a,100000000)` mediumtext
+) ENGINE=MyISAM DEFAULT CHARSET=latin1
+drop tables t1,t2,t3;
+CREATE TABLE t1 (a longtext);
+CREATE TABLE t2 (b varchar(20));
+INSERT INTO t1 VALUES ('a'),('b');
+SELECT left(a,100000000) FROM t1 UNION  SELECT b FROM t2;
+left(a,100000000)
+a
+b
+create table t3 SELECT left(a,100000000) FROM t1 UNION  SELECT b FROM t2;
+show create table t3;
+Table	Create Table
 t3	CREATE TABLE `t3` (
   `left(a,100000000)` longtext
 ) ENGINE=MyISAM DEFAULT CHARSET=latin1
 drop tables t1,t2,t3;
+SELECT @tmp_max:= @@max_allowed_packet;
+@tmp_max:= @@max_allowed_packet
+1048576
+SET max_allowed_packet=25000000;
+CREATE TABLE t1 (a mediumtext);
+CREATE TABLE t2 (b varchar(20));
+INSERT INTO t1 VALUES ('a');
+CREATE TABLE t3 SELECT REPEAT(a,20000000) AS a FROM t1 UNION SELECT b FROM t2;
+SHOW CREATE TABLE t3;
+Table	Create Table
+t3	CREATE TABLE `t3` (
+  `a` longtext
+) ENGINE=MyISAM DEFAULT CHARSET=latin1
+DROP TABLES t1,t2,t3;
+SET max_allowed_packet:= @tmp_max;
 create table t1 ( id int not null auto_increment, primary key (id), col1 int);
 insert into t1 (col1) values (2),(3),(4),(5),(6);
 select 99 union all select id from t1 order by 1;
diff --git a/mysql-test/t/union.test b/mysql-test/t/union.test
index bf5c5e066f0..b510877d23d 100644
--- a/mysql-test/t/union.test
+++ b/mysql-test/t/union.test
@@ -774,6 +774,7 @@ drop table t1,t2;
 #
 # correct conversion long string to TEXT (BUG#10025)
 #
+
 CREATE TABLE t1 (a mediumtext);
 CREATE TABLE t2 (b varchar(20));
 INSERT INTO t1 VALUES ('a'),('b');
@@ -782,6 +783,35 @@ create table t3 SELECT left(a,100000000) FROM t1 UNION  SELECT b FROM t2;
 show create table t3;
 drop tables t1,t2,t3;
 
+#
+# Extended fix to Bug#10025 - the test above should result to mediumtext
+# and the one below to longtext. Earlier above test resulted to longtext
+# type also.
+#
+
+CREATE TABLE t1 (a longtext);
+CREATE TABLE t2 (b varchar(20));
+INSERT INTO t1 VALUES ('a'),('b');
+SELECT left(a,100000000) FROM t1 UNION  SELECT b FROM t2;
+create table t3 SELECT left(a,100000000) FROM t1 UNION  SELECT b FROM t2;
+show create table t3;
+drop tables t1,t2,t3;
+
+#
+# Testing here that mediumtext converts into longtext if the result
+# exceeds mediumtext maximum length
+#
+
+SELECT @tmp_max:= @@max_allowed_packet;
+SET max_allowed_packet=25000000;
+CREATE TABLE t1 (a mediumtext);
+CREATE TABLE t2 (b varchar(20));
+INSERT INTO t1 VALUES ('a');
+CREATE TABLE t3 SELECT REPEAT(a,20000000) AS a FROM t1 UNION SELECT b FROM t2;
+SHOW CREATE TABLE t3;
+DROP TABLES t1,t2,t3;
+SET max_allowed_packet:= @tmp_max;
+
 #
 # Bug #10032 Bug in parsing UNION with ORDER BY when one node does not use FROM
 #