4 files changed, 96 insertions, 2 deletions

diff --git a/mysql-test/main/mysql_upgrade.result b/mysql-test/main/mysql_upgrade.result
index 75566d06a0c..9ed34ad9028 100644
--- a/mysql-test/main/mysql_upgrade.result
+++ b/mysql-test/main/mysql_upgrade.result
@@ -947,4 +947,42 @@ disconnect con1;
 connection default;
 drop table mysql.global_priv;
 rename table mysql.global_priv_bak to mysql.global_priv;
+#
+# MDEV-28727 ALTER TABLE ALGORITHM=NOCOPY does not work after upgrade
+#
+create or replace table pet4 (
+build_time double(18, 7) default null,
+key idx1 (build_time)
+) engine innodb;
+check table pet4;
+Table	Op	Msg_type	Msg_text
+test.pet4	check	error	Table rebuild required. Please do "ALTER TABLE `pet4` FORCE" or dump/reload to fix it!
+check table pet4 for upgrade;
+Table	Op	Msg_type	Msg_text
+test.pet4	check	error	Table rebuild required. Please do "ALTER TABLE `pet4` FORCE" or dump/reload to fix it!
+alter table pet4 add i1 int, algorithm=nocopy;
+ERROR 0A000: ALGORITHM=NOCOPY is not supported for this operation. Try ALGORITHM=INPLACE
+# Running mysqlcheck
+test.pet4
+error    : Table rebuild required. Please do "ALTER TABLE `pet4` FORCE" or dump/reload to fix it!
+
+Repairing tables
+check table pet4;
+Table	Op	Msg_type	Msg_text
+test.pet4	check	status	OK
+alter table pet4 add i1 int, algorithm=nocopy;
+create or replace table pet4 (
+build_time double(18, 7) default null,
+key idx1 (build_time)
+) engine innodb;
+alter table pet4 add i1 int, algorithm=nocopy;
+ERROR 0A000: ALGORITHM=NOCOPY is not supported for this operation. Try ALGORITHM=INPLACE
+# Running mysql_upgrade
+test.pet4
+error    : Table rebuild required. Please do "ALTER TABLE `pet4` FORCE" or dump/reload to fix it!
+check table pet4;
+Table	Op	Msg_type	Msg_text
+test.pet4	check	status	OK
+alter table pet4 add i1 int, algorithm=nocopy;
+drop table pet4;
 # End of 10.4 tests
diff --git a/mysql-test/main/mysql_upgrade.test b/mysql-test/main/mysql_upgrade.test
index 0440cd75d77..b0a1ffaa9d9 100644
--- a/mysql-test/main/mysql_upgrade.test
+++ b/mysql-test/main/mysql_upgrade.test
@@ -471,4 +471,45 @@ drop table mysql.global_priv;
 rename table mysql.global_priv_bak to mysql.global_priv;
 --remove_file $MYSQLD_DATADIR/mysql_upgrade_info
 
+--echo #
+--echo # MDEV-28727 ALTER TABLE ALGORITHM=NOCOPY does not work after upgrade
+--echo #
+create or replace table pet4 (
+  build_time double(18, 7) default null,
+  key idx1 (build_time)
+) engine innodb;
+
+--remove_file $MYSQLD_DATADIR/test/pet4.frm
+--copy_file std_data/mdev-28727-pet4.frm $MYSQLD_DATADIR/test/pet4.frm
+
+check table pet4;
+check table pet4 for upgrade;
+--error ER_ALTER_OPERATION_NOT_SUPPORTED
+alter table pet4 add i1 int, algorithm=nocopy;
+
+--echo # Running mysqlcheck
+--exec $MYSQL_CHECK --auto-repair --databases test 2>&1
+check table pet4;
+alter table pet4 add i1 int, algorithm=nocopy;
+
+create or replace table pet4 (
+  build_time double(18, 7) default null,
+  key idx1 (build_time)
+) engine innodb;
+
+--remove_file $MYSQLD_DATADIR/test/pet4.frm
+--copy_file std_data/mdev-28727-pet4.frm $MYSQLD_DATADIR/test/pet4.frm
+
+--error ER_ALTER_OPERATION_NOT_SUPPORTED
+alter table pet4 add i1 int, algorithm=nocopy;
+
+--echo # Running mysql_upgrade
+--exec $MYSQL_UPGRADE --silent 2>&1
+file_exists $MYSQLD_DATADIR/mysql_upgrade_info;
+check table pet4;
+alter table pet4 add i1 int, algorithm=nocopy;
+
+--remove_file $MYSQLD_DATADIR/mysql_upgrade_info
+drop table pet4;
+
 --echo # End of 10.4 tests
diff --git a/mysql-test/std_data/mdev-28727-pet4.frm b/mysql-test/std_data/mdev-28727-pet4.frm
new file mode 100644
index 00000000000..3ff86d1dca1
--- /dev/null
+++ b/mysql-test/std_data/mdev-28727-pet4.frm
diff --git a/sql/handler.cc b/sql/handler.cc
index bf819733b81..e6e665f0e12 100644
--- a/sql/handler.cc
+++ b/sql/handler.cc
@@ -4370,17 +4370,32 @@ int handler::ha_check(THD *thd, HA_CHECK_OPT *check_opt)
   DBUG_ASSERT(table_share->tmp_table != NO_TMP_TABLE ||
               m_lock_type != F_UNLCK);
 
-  if ((table->s->mysql_version >= MYSQL_VERSION_ID) &&
+  const ulong v= table->s->mysql_version;
+
+  if ((v >= MYSQL_VERSION_ID) &&
       (check_opt->sql_flags & TT_FOR_UPGRADE))
     return 0;
 
-  if (table->s->mysql_version < MYSQL_VERSION_ID)
+  if (v < MYSQL_VERSION_ID)
   {
     if (unlikely((error= check_old_types())))
       return error;
     error= ha_check_for_upgrade(check_opt);
     if (unlikely(error && (error != HA_ADMIN_NEEDS_CHECK)))
       return error;
+    if (table->s->table_category == TABLE_CATEGORY_USER &&
+        (v < 100142 ||
+         (v >= 100200 && v < 100228) ||
+         (v >= 100300 && v < 100319) ||
+         (v >= 100400 && v < 100409)))
+    {
+      for (const KEY *key= table->key_info,
+           *end= table->key_info + table->s->keys; key < end; key++)
+      {
+        if (key->flags & HA_BINARY_PACK_KEY && key->flags & HA_VAR_LENGTH_KEY)
+          return HA_ADMIN_NEEDS_UPGRADE;
+      }
+    }
     if (unlikely(!error && (check_opt->sql_flags & TT_FOR_UPGRADE)))
       return 0;
   }