BUG#25877, After DROP INDEX non-indexed data isn't moved from memory into tablespace

sql/ha_ndbcluster.cc:
  add/drop index online will change storage media type, 
  so add storage type check in check_if_incompatible_data(),
  when storage type is changed, will create a new table,
  then this can correct the column and table's storage type.

sql/ha_ndbcluster.cc

@@ -10606,10 +10606,23 @@ bool ha_ndbcluster::check_if_incompatible_data(HA_CREATE_INFO *create_info,
 
   int pk= 0;
   int ai= 0;
+
+  if (create_info->tablespace)
+    create_info->storage_media = HA_SM_DISK;
+  else
+    create_info->storage_media = HA_SM_MEMORY;
+
   for (i= 0; i < table->s->fields; i++) 
   {
     Field *field= table->field[i];
     const NDBCOL *col= tab->getColumn(i);
+    if (col->getStorageType() == NDB_STORAGETYPE_MEMORY && create_info->storage_media != HA_SM_MEMORY ||
+        col->getStorageType() == NDB_STORAGETYPE_DISK && create_info->storage_media != HA_SM_DISK)
+    {
+      DBUG_PRINT("info", ("Column storage media is changed"));
+      DBUG_RETURN(COMPATIBLE_DATA_NO);
+    }
+    
     if (field->flags & FIELD_IS_RENAMED)
     {
       DBUG_PRINT("info", ("Field has been renamed, copy table"));