diff --git a/mysql-test/r/innodb_mysql.result b/mysql-test/r/innodb_mysql.result
index 029f3768f9b..93b93c6253c 100644
--- a/mysql-test/r/innodb_mysql.result
+++ b/mysql-test/r/innodb_mysql.result
@@ -182,4 +182,40 @@ t1.a4='UNcT5pIde4I6c2SheTo4gt92OV1jgJCVkXmzyf325R1DwLURkbYHwhydANIZMbKTgdcR5xS';
 id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
 1	SIMPLE	NULL	NULL	NULL	NULL	NULL	NULL	NULL	Impossible WHERE noticed after reading const tables
 DROP TABLE t1;
+CREATE TABLE t1 (a CHAR(2), KEY (a)) ENGINE = InnoDB DEFAULT CHARSET=UTF8;
+INSERT INTO t1 VALUES ('uk'),('bg');
+SELECT * FROM t1 WHERE a = 'uk';
+a
+uk
+DELETE FROM t1 WHERE a = 'uk';
+SELECT * FROM t1 WHERE a = 'uk';
+a
+UPDATE t1 SET a = 'us' WHERE a = 'uk';
+SELECT * FROM t1 WHERE a = 'uk';
+a
+CREATE TABLE t2 (a CHAR(2), KEY (a)) ENGINE = InnoDB;
+INSERT INTO t2 VALUES ('uk'),('bg');
+SELECT * FROM t2 WHERE a = 'uk';
+a
+uk
+DELETE FROM t2 WHERE a = 'uk';
+SELECT * FROM t2 WHERE a = 'uk';
+a
+INSERT INTO t2 VALUES ('uk');
+UPDATE t2 SET a = 'us' WHERE a = 'uk';
+SELECT * FROM t2 WHERE a = 'uk';
+a
+CREATE TABLE t3 (a CHAR(2), KEY (a)) ENGINE = MyISAM;
+INSERT INTO t3 VALUES ('uk'),('bg');
+SELECT * FROM t3 WHERE a = 'uk';
+a
+uk
+DELETE FROM t3 WHERE a = 'uk';
+SELECT * FROM t3 WHERE a = 'uk';
+a
+INSERT INTO t3 VALUES ('uk');
+UPDATE t3 SET a = 'us' WHERE a = 'uk';
+SELECT * FROM t3 WHERE a = 'uk';
+a
+DROP TABLE t1,t2,t3;
 End of 4.1 tests
diff --git a/mysql-test/t/innodb_mysql.test b/mysql-test/t/innodb_mysql.test
index b5e7fc6e405..4e20535549a 100644
--- a/mysql-test/t/innodb_mysql.test
+++ b/mysql-test/t/innodb_mysql.test
@@ -216,4 +216,36 @@ t1.a4='UNcT5pIde4I6c2SheTo4gt92OV1jgJCVkXmzyf325R1DwLURkbYHwhydANIZMbKTgdcR5xS';
 
 DROP TABLE t1;
 
+#
+# Bug #28878: InnoDB tables with UTF8 character set and indexes cause wrong result for DML
+#
+
+CREATE TABLE t1 (a CHAR(2), KEY (a)) ENGINE = InnoDB DEFAULT CHARSET=UTF8;
+INSERT INTO t1 VALUES ('uk'),('bg');
+SELECT * FROM t1 WHERE a = 'uk';
+DELETE FROM t1 WHERE a = 'uk';
+SELECT * FROM t1 WHERE a = 'uk';
+UPDATE t1 SET a = 'us' WHERE a = 'uk';
+SELECT * FROM t1 WHERE a = 'uk';
+
+CREATE TABLE t2 (a CHAR(2), KEY (a)) ENGINE = InnoDB;
+INSERT INTO t2 VALUES ('uk'),('bg');
+SELECT * FROM t2 WHERE a = 'uk';
+DELETE FROM t2 WHERE a = 'uk';
+SELECT * FROM t2 WHERE a = 'uk';
+INSERT INTO t2 VALUES ('uk');
+UPDATE t2 SET a = 'us' WHERE a = 'uk';
+SELECT * FROM t2 WHERE a = 'uk';
+
+CREATE TABLE t3 (a CHAR(2), KEY (a)) ENGINE = MyISAM;
+INSERT INTO t3 VALUES ('uk'),('bg');
+SELECT * FROM t3 WHERE a = 'uk';
+DELETE FROM t3 WHERE a = 'uk';
+SELECT * FROM t3 WHERE a = 'uk';
+INSERT INTO t3 VALUES ('uk');
+UPDATE t3 SET a = 'us' WHERE a = 'uk';
+SELECT * FROM t3 WHERE a = 'uk';
+
+DROP TABLE t1,t2,t3;
+
 --echo End of 4.1 tests
diff --git a/sql/field.cc b/sql/field.cc
index 1b27e12e078..5b43b9b1955 100644
--- a/sql/field.cc
+++ b/sql/field.cc
@@ -5211,7 +5211,8 @@ uint Field_string::get_key_image(char *buff, uint length, CHARSET_INFO *cs,
                           length / field_charset->mbmaxlen);
   memcpy(buff, ptr, bytes);
   if (bytes < length)
-    bzero(buff + bytes, length - bytes);
+    field_charset->cset->fill(field_charset, buff + bytes, length - bytes,
+                              ' ');
   return bytes;
 }