diff --git a/include/maria.h b/include/maria.h
index 880b7367c0b..a1396d3a4c7 100644
--- a/include/maria.h
+++ b/include/maria.h
@@ -305,7 +305,7 @@ extern int maria_rsame_with_pos(MARIA_HA *file, uchar *record,
 				int inx, MARIA_RECORD_POS pos);
 extern int maria_update(MARIA_HA *file, const uchar *old,
 			const uchar *new_record);
-extern int maria_write(MARIA_HA *file, uchar *buff);
+extern int maria_write(MARIA_HA *file, const uchar *buff);
 extern MARIA_RECORD_POS maria_position(MARIA_HA *file);
 extern int maria_status(MARIA_HA *info, MARIA_INFO *x, uint flag);
 extern int maria_lock_database(MARIA_HA *file, int lock_type);
diff --git a/include/myisam.h b/include/myisam.h
index 3138dc832f7..216f041c8a9 100644
--- a/include/myisam.h
+++ b/include/myisam.h
@@ -276,7 +276,7 @@ extern int mi_rsame_with_pos(struct st_myisam_info *file,uchar *record,
 			     int inx, my_off_t pos);
 extern int mi_update(struct st_myisam_info *file,const uchar *old,
 		     const uchar *new_record);
-extern int mi_write(struct st_myisam_info *file,uchar *buff);
+extern int mi_write(struct st_myisam_info *file,const uchar *buff);
 extern my_off_t mi_position(struct st_myisam_info *file);
 extern int mi_status(struct st_myisam_info *info, MI_ISAMINFO *x, uint flag);
 extern int mi_lock_database(struct st_myisam_info *file,int lock_type);
diff --git a/include/myisammrg.h b/include/myisammrg.h
index fe229a85cb0..76286000ff5 100644
--- a/include/myisammrg.h
+++ b/include/myisammrg.h
@@ -106,7 +106,7 @@ extern int myrg_rrnd(MYRG_INFO *file,uchar *buf,ulonglong pos);
 extern int myrg_rsame(MYRG_INFO *file,uchar *record,int inx);
 extern int myrg_update(MYRG_INFO *file,const uchar *old,
                        const uchar *new_rec);
-extern int myrg_write(MYRG_INFO *info,uchar *rec);
+extern int myrg_write(MYRG_INFO *info,const uchar *rec);
 extern int myrg_status(MYRG_INFO *file,MYMERGE_INFO *x,int flag);
 extern int myrg_lock_database(MYRG_INFO *file,int lock_type);
 extern int myrg_create(const char *name, const char **table_names,
diff --git a/sql/field.h b/sql/field.h
index 0af2150adfa..708a2d88b61 100644
--- a/sql/field.h
+++ b/sql/field.h
@@ -1364,7 +1364,7 @@ public:
   virtual uint max_packed_col_length(uint max_length)
   { return max_length;}
 
-  uint offset(uchar *record) const
+  uint offset(const uchar *record) const
   {
     return (uint) (ptr - record);
   }
diff --git a/sql/ha_partition.cc b/sql/ha_partition.cc
index 8a0b9822493..75f6585f847 100644
--- a/sql/ha_partition.cc
+++ b/sql/ha_partition.cc
@@ -4247,7 +4247,7 @@ void ha_partition::try_semi_consistent_read(bool yes)
     determining which partition the row should be written to.
 */
 
-int ha_partition::write_row(uchar * buf)
+int ha_partition::write_row(const uchar * buf)
 {
   uint32 part_id;
   int error;
diff --git a/sql/ha_partition.h b/sql/ha_partition.h
index 18468268077..de5b4f2a66f 100644
--- a/sql/ha_partition.h
+++ b/sql/ha_partition.h
@@ -628,7 +628,7 @@ public:
     start_bulk_insert and end_bulk_insert is called before and after a
     number of calls to write_row.
   */
-  virtual int write_row(uchar * buf);
+  virtual int write_row(const uchar * buf);
   virtual bool start_bulk_update();
   virtual int exec_bulk_update(ha_rows *dup_key_found);
   virtual int end_bulk_update();
diff --git a/sql/ha_sequence.cc b/sql/ha_sequence.cc
index 65bb0daf8cf..beaed6ef7df 100644
--- a/sql/ha_sequence.cc
+++ b/sql/ha_sequence.cc
@@ -194,7 +194,7 @@ int ha_sequence::create(const char *name, TABLE *form,
     the sequence with 'buf' as the sequence object is already up to date.
 */
 
-int ha_sequence::write_row(uchar *buf)
+int ha_sequence::write_row(const uchar *buf)
 {
   int error;
   sequence_definition tmp_seq;
diff --git a/sql/ha_sequence.h b/sql/ha_sequence.h
index fd9da05b591..4360e9faa3d 100644
--- a/sql/ha_sequence.h
+++ b/sql/ha_sequence.h
@@ -71,7 +71,7 @@ public:
   int create(const char *name, TABLE *form,
              HA_CREATE_INFO *create_info);
   handler *clone(const char *name, MEM_ROOT *mem_root);
-  int write_row(uchar *buf);
+  int write_row(const uchar *buf);
   Table_flags table_flags() const;
   /* One can't update or delete from sequence engine */
   int update_row(const uchar *old_data, const uchar *new_data)
diff --git a/sql/handler.cc b/sql/handler.cc
index 0b8d881a0a7..c4f5febbdcf 100644
--- a/sql/handler.cc
+++ b/sql/handler.cc
@@ -6499,7 +6499,7 @@ static int wsrep_after_row(THD *thd)
 #endif /* WITH_WSREP */
 
 static int check_duplicate_long_entry_key(TABLE *table, handler *h,
-                                          uchar *new_rec, uint key_no)
+                                          const uchar *new_rec, uint key_no)
 {
   Field *hash_field;
   int result, error= 0;
@@ -6588,7 +6588,8 @@ exit:
     unique constraint on long columns.
     @returns 0 if no duplicate else returns error
   */
-static int check_duplicate_long_entries(TABLE *table, handler *h, uchar *new_rec)
+static int check_duplicate_long_entries(TABLE *table, handler *h,
+                                        const uchar *new_rec)
 {
   table->file->errkey= -1;
   int result;
@@ -6657,7 +6658,7 @@ static int check_duplicate_long_entries_update(TABLE *table, handler *h, uchar *
   return error;
 }
 
-int handler::ha_write_row(uchar *buf)
+int handler::ha_write_row(const uchar *buf)
 {
   int error;
   Log_func *log_func= Write_rows_log_event::binlog_row_logging_function;
@@ -6746,7 +6747,7 @@ int handler::ha_update_row(const uchar *old_data, const uchar *new_data)
   Update first row. Only used by sequence tables
 */
 
-int handler::update_first_row(uchar *new_data)
+int handler::update_first_row(const uchar *new_data)
 {
   int error;
   if (likely(!(error= ha_rnd_init(1))))
diff --git a/sql/handler.h b/sql/handler.h
index e144cbc6642..7bdcb637485 100644
--- a/sql/handler.h
+++ b/sql/handler.h
@@ -3238,7 +3238,7 @@ public:
     and delete_row() below.
   */
   int ha_external_lock(THD *thd, int lock_type);
-  int ha_write_row(uchar * buf);
+  int ha_write_row(const uchar * buf);
   int ha_update_row(const uchar * old_data, const uchar * new_data);
   int ha_delete_row(const uchar * buf);
   void ha_release_auto_increment();
@@ -4548,7 +4548,7 @@ private:
   */
   virtual int rnd_init(bool scan)= 0;
   virtual int rnd_end() { return 0; }
-  virtual int write_row(uchar *buf __attribute__((unused)))
+  virtual int write_row(const uchar *buf __attribute__((unused)))
   {
     return HA_ERR_WRONG_COMMAND;
   }
@@ -4571,7 +4571,7 @@ private:
     Optimized function for updating the first row. Only used by sequence
     tables
   */
-  virtual int update_first_row(uchar *new_data);
+  virtual int update_first_row(const uchar *new_data);
 
   virtual int delete_row(const uchar *buf __attribute__((unused)))
   {
diff --git a/storage/archive/ha_archive.cc b/storage/archive/ha_archive.cc
index 0cf9763a0ee..fa49b081ad1 100644
--- a/storage/archive/ha_archive.cc
+++ b/storage/archive/ha_archive.cc
@@ -371,7 +371,7 @@ int Archive_share::write_v1_metafile()
   @return Length of packed row
 */
 
-unsigned int ha_archive::pack_row_v1(uchar *record)
+unsigned int ha_archive::pack_row_v1(const uchar *record)
 {
   uint *blob, *end;
   uchar *pos;
@@ -868,7 +868,7 @@ error:
 /*
   This is where the actual row is written out.
 */
-int ha_archive::real_write_row(uchar *buf, azio_stream *writer)
+int ha_archive::real_write_row(const uchar *buf, azio_stream *writer)
 {
   my_off_t written;
   unsigned int r_pack_length;
@@ -917,7 +917,7 @@ uint32 ha_archive::max_row_length(const uchar *record)
 }
 
 
-unsigned int ha_archive::pack_row(uchar *record, azio_stream *writer)
+unsigned int ha_archive::pack_row(const uchar *record, azio_stream *writer)
 {
   uchar *ptr;
   my_ptrdiff_t const rec_offset= record - table->record[0];
@@ -959,7 +959,7 @@ unsigned int ha_archive::pack_row(uchar *record, azio_stream *writer)
   for implementing start_bulk_insert() is that we could skip 
   setting dirty to true each time.
 */
-int ha_archive::write_row(uchar *buf)
+int ha_archive::write_row(const uchar *buf)
 {
   int rc;
   uchar *read_buf= NULL;
diff --git a/storage/archive/ha_archive.h b/storage/archive/ha_archive.h
index 043eab2670a..b9fcf10f96f 100644
--- a/storage/archive/ha_archive.h
+++ b/storage/archive/ha_archive.h
@@ -95,7 +95,7 @@ class ha_archive: public handler
   void destroy_record_buffer(archive_record_buffer *r);
   int frm_copy(azio_stream *src, azio_stream *dst);
   int frm_compare(azio_stream *src);
-  unsigned int pack_row_v1(uchar *record);
+  unsigned int pack_row_v1(const uchar *record);
 
 public:
   ha_archive(handlerton *hton, TABLE_SHARE *table_arg);
@@ -131,8 +131,8 @@ public:
   int index_next(uchar * buf);
   int open(const char *name, int mode, uint test_if_locked);
   int close(void);
-  int write_row(uchar * buf);
-  int real_write_row(uchar *buf, azio_stream *writer);
+  int write_row(const uchar * buf);
+  int real_write_row(const uchar *buf, azio_stream *writer);
   int truncate();
   int rnd_init(bool scan=1);
   int rnd_next(uchar *buf);
@@ -168,7 +168,7 @@ public:
   uint32 max_row_length(const uchar *buf);
   bool fix_rec_buff(unsigned int length);
   int unpack_row(azio_stream *file_to_read, uchar *record);
-  unsigned int pack_row(uchar *record, azio_stream *writer);
+  unsigned int pack_row(const uchar *record, azio_stream *writer);
   bool check_if_incompatible_data(HA_CREATE_INFO *info, uint table_changes);
   int external_lock(THD *thd, int lock_type);
 private:
diff --git a/storage/blackhole/ha_blackhole.cc b/storage/blackhole/ha_blackhole.cc
index 3f770c7005e..1b64db142e0 100644
--- a/storage/blackhole/ha_blackhole.cc
+++ b/storage/blackhole/ha_blackhole.cc
@@ -117,7 +117,7 @@ const char *ha_blackhole::index_type(uint key_number)
                HA_KEY_ALG_RTREE) ? "RTREE" : "BTREE");
 }
 
-int ha_blackhole::write_row(uchar * buf)
+int ha_blackhole::write_row(const uchar * buf)
 {
   DBUG_ENTER("ha_blackhole::write_row");
   DBUG_RETURN(table->next_number_field ? update_auto_increment() : 0);
diff --git a/storage/blackhole/ha_blackhole.h b/storage/blackhole/ha_blackhole.h
index 0632c87c306..6ee30877b64 100644
--- a/storage/blackhole/ha_blackhole.h
+++ b/storage/blackhole/ha_blackhole.h
@@ -96,7 +96,7 @@ public:
                              THR_LOCK_DATA **to,
                              enum thr_lock_type lock_type);
 private:
-  virtual int write_row(uchar *buf);
+  virtual int write_row(const uchar *buf);
   virtual int update_row(const uchar *old_data, const uchar *new_data);
   virtual int delete_row(const uchar *buf);
 };
diff --git a/storage/cassandra/ha_cassandra.cc b/storage/cassandra/ha_cassandra.cc
index 4f9e207235f..f081dca71c3 100644
--- a/storage/cassandra/ha_cassandra.cc
+++ b/storage/cassandra/ha_cassandra.cc
@@ -1931,7 +1931,7 @@ void ha_cassandra::free_dynamic_row(DYNAMIC_COLUMN_VALUE **vals,
   *names= 0;
 }
 
-int ha_cassandra::write_row(uchar *buf)
+int ha_cassandra::write_row(const uchar *buf)
 {
   my_bitmap_map *old_map;
   int ires;
diff --git a/storage/cassandra/ha_cassandra.h b/storage/cassandra/ha_cassandra.h
index 9a44abc985f..a36d58fa4da 100644
--- a/storage/cassandra/ha_cassandra.h
+++ b/storage/cassandra/ha_cassandra.h
@@ -239,7 +239,7 @@ public:
   int open(const char *name, int mode, uint test_if_locked);
   int close(void);
 
-  int write_row(uchar *buf);
+  int write_row(const uchar *buf);
   int update_row(const uchar *old_data, const uchar *new_data);
   int delete_row(const uchar *buf);
 
diff --git a/storage/connect/ha_connect.cc b/storage/connect/ha_connect.cc
index 9a154cf1af2..b1eddc29dff 100644
--- a/storage/connect/ha_connect.cc
+++ b/storage/connect/ha_connect.cc
@@ -3576,7 +3576,7 @@ int ha_connect::close(void)
   item_sum.cc, item_sum.cc, sql_acl.cc, sql_insert.cc,
   sql_insert.cc, sql_select.cc, sql_table.cc, sql_udf.cc and sql_update.cc
 */
-int ha_connect::write_row(uchar *buf)
+int ha_connect::write_row(const uchar *buf)
 {
   int      rc= 0;
   PGLOBAL& g= xp->g;
diff --git a/storage/connect/ha_connect.h b/storage/connect/ha_connect.h
index 5a1dcb1a88f..53e666d534d 100644
--- a/storage/connect/ha_connect.h
+++ b/storage/connect/ha_connect.h
@@ -388,7 +388,7 @@ virtual int check(THD* thd, HA_CHECK_OPT* check_opt);
     We implement this in ha_connect.cc. It's not an obligatory method;
     skip it and and MySQL will treat it as not implemented.
   */
-  int write_row(uchar *buf);
+  int write_row(const uchar *buf);
 
   /** @brief
     We implement this in ha_connect.cc. It's not an obligatory method;
diff --git a/storage/csv/ha_tina.cc b/storage/csv/ha_tina.cc
index 3ff3b5bd1ba..badb515c2b2 100644
--- a/storage/csv/ha_tina.cc
+++ b/storage/csv/ha_tina.cc
@@ -1004,7 +1004,7 @@ int ha_tina::close(void)
   of the file and appends the data. In an error case it really should
   just truncate to the original position (this is not done yet).
 */
-int ha_tina::write_row(uchar * buf)
+int ha_tina::write_row(const uchar * buf)
 {
   int size;
   DBUG_ENTER("ha_tina::write_row");
diff --git a/storage/csv/ha_tina.h b/storage/csv/ha_tina.h
index efb161a714e..aae535c271e 100644
--- a/storage/csv/ha_tina.h
+++ b/storage/csv/ha_tina.h
@@ -136,7 +136,7 @@ public:
 
   int open(const char *name, int mode, uint open_options);
   int close(void);
-  int write_row(uchar * buf);
+  int write_row(const uchar * buf);
   int update_row(const uchar * old_data, const uchar * new_data);
   int delete_row(const uchar * buf);
   int rnd_init(bool scan=1);
diff --git a/storage/example/ha_example.cc b/storage/example/ha_example.cc
index 643fa1ae09a..d5d7594791e 100644
--- a/storage/example/ha_example.cc
+++ b/storage/example/ha_example.cc
@@ -398,7 +398,7 @@ int ha_example::close(void)
   sql_insert.cc, sql_select.cc, sql_table.cc, sql_udf.cc and sql_update.cc
 */
 
-int ha_example::write_row(uchar *buf)
+int ha_example::write_row(const uchar *buf)
 {
   DBUG_ENTER("ha_example::write_row");
   /*
diff --git a/storage/example/ha_example.h b/storage/example/ha_example.h
index 52fb4ff3c1b..0a08e871461 100644
--- a/storage/example/ha_example.h
+++ b/storage/example/ha_example.h
@@ -180,7 +180,7 @@ public:
     We implement this in ha_example.cc. It's not an obligatory method;
     skip it and and MySQL will treat it as not implemented.
   */
-  int write_row(uchar *buf);
+  int write_row(const uchar *buf);
 
   /** @brief
     We implement this in ha_example.cc. It's not an obligatory method;
diff --git a/storage/federated/ha_federated.cc b/storage/federated/ha_federated.cc
index 79e70ce5123..ec34cf16858 100644
--- a/storage/federated/ha_federated.cc
+++ b/storage/federated/ha_federated.cc
@@ -1825,7 +1825,7 @@ bool ha_federated::append_stmt_insert(String *query)
   sql_insert.cc, sql_select.cc, sql_table.cc, sql_udf.cc, and sql_update.cc.
 */
 
-int ha_federated::write_row(uchar *buf)
+int ha_federated::write_row(const uchar *buf)
 {
   char values_buffer[FEDERATED_QUERY_BUFFER_SIZE];
   char insert_field_value_buffer[STRING_BUFFER_USUAL_SIZE];
diff --git a/storage/federated/ha_federated.h b/storage/federated/ha_federated.h
index fc379707703..3beb2ca9570 100644
--- a/storage/federated/ha_federated.h
+++ b/storage/federated/ha_federated.h
@@ -209,7 +209,7 @@ public:
 
   void start_bulk_insert(ha_rows rows, uint flags);
   int end_bulk_insert();
-  int write_row(uchar *buf);
+  int write_row(const uchar *buf);
   int update_row(const uchar *old_data, const uchar *new_data);
   int delete_row(const uchar *buf);
   int index_init(uint keynr, bool sorted);
diff --git a/storage/federatedx/ha_federatedx.cc b/storage/federatedx/ha_federatedx.cc
index b0a08a0d49a..bea7f2cfb87 100644
--- a/storage/federatedx/ha_federatedx.cc
+++ b/storage/federatedx/ha_federatedx.cc
@@ -1987,7 +1987,7 @@ bool ha_federatedx::append_stmt_insert(String *query)
   sql_insert.cc, sql_select.cc, sql_table.cc, sql_udf.cc, and sql_update.cc.
 */
 
-int ha_federatedx::write_row(uchar *buf)
+int ha_federatedx::write_row(const uchar *buf)
 {
   char values_buffer[FEDERATEDX_QUERY_BUFFER_SIZE];
   char insert_field_value_buffer[STRING_BUFFER_USUAL_SIZE];
diff --git a/storage/federatedx/ha_federatedx.h b/storage/federatedx/ha_federatedx.h
index 67aa83f7b33..1870a83d13d 100644
--- a/storage/federatedx/ha_federatedx.h
+++ b/storage/federatedx/ha_federatedx.h
@@ -397,7 +397,7 @@ public:
 
   void start_bulk_insert(ha_rows rows, uint flags);
   int end_bulk_insert();
-  int write_row(uchar *buf);
+  int write_row(const uchar *buf);
   int update_row(const uchar *old_data, const uchar *new_data);
   int delete_row(const uchar *buf);
   int index_init(uint keynr, bool sorted);
diff --git a/storage/heap/ha_heap.cc b/storage/heap/ha_heap.cc
index 73857a14a2f..acc835cf300 100644
--- a/storage/heap/ha_heap.cc
+++ b/storage/heap/ha_heap.cc
@@ -228,7 +228,7 @@ void ha_heap::update_key_stats()
 }
 
 
-int ha_heap::write_row(uchar * buf)
+int ha_heap::write_row(const uchar * buf)
 {
   int res;
   if (table->next_number_field && buf == table->record[0])
diff --git a/storage/heap/ha_heap.h b/storage/heap/ha_heap.h
index 0d2a7a3a442..3440c8fd205 100644
--- a/storage/heap/ha_heap.h
+++ b/storage/heap/ha_heap.h
@@ -70,7 +70,7 @@ public:
   int open(const char *name, int mode, uint test_if_locked);
   int close(void);
   void set_keys_for_scanning(void);
-  int write_row(uchar * buf);
+  int write_row(const uchar * buf);
   int update_row(const uchar * old_data, const uchar * new_data);
   int delete_row(const uchar * buf);
   virtual void get_auto_increment(ulonglong offset, ulonglong increment,
diff --git a/storage/innobase/handler/ha_innodb.cc b/storage/innobase/handler/ha_innodb.cc
index ada0e8b1773..4898e1527dc 100644
--- a/storage/innobase/handler/ha_innodb.cc
+++ b/storage/innobase/handler/ha_innodb.cc
@@ -7997,7 +7997,7 @@ handle.
 int
 ha_innobase::write_row(
 /*===================*/
-	uchar*	record)	/*!< in: a row in MySQL format */
+	const uchar*	record)	/*!< in: a row in MySQL format */
 {
 	dberr_t		error;
 #ifdef WITH_WSREP
diff --git a/storage/innobase/handler/ha_innodb.h b/storage/innobase/handler/ha_innodb.h
index cffd1683a67..a0ce93bec3c 100644
--- a/storage/innobase/handler/ha_innodb.h
+++ b/storage/innobase/handler/ha_innodb.h
@@ -112,7 +112,7 @@ public:
 
 	int delete_all_rows() override;
 
-	int write_row(uchar * buf) override;
+	int write_row(const uchar * buf) override;
 
 	int update_row(const uchar * old_data, const uchar * new_data) override;
 
diff --git a/storage/maria/ha_maria.cc b/storage/maria/ha_maria.cc
index 54a1d1ce146..496f6006aa1 100644
--- a/storage/maria/ha_maria.cc
+++ b/storage/maria/ha_maria.cc
@@ -1227,7 +1227,7 @@ int ha_maria::close(void)
 }
 
 
-int ha_maria::write_row(uchar * buf)
+int ha_maria::write_row(const uchar * buf)
 {
   /*
      If we have an auto_increment column and we are writing a changed row
diff --git a/storage/maria/ha_maria.h b/storage/maria/ha_maria.h
index 48af840d86b..ef0ceb1cd32 100644
--- a/storage/maria/ha_maria.h
+++ b/storage/maria/ha_maria.h
@@ -73,7 +73,7 @@ public:
 
   int open(const char *name, int mode, uint test_if_locked);
   int close(void);
-  int write_row(uchar * buf);
+  int write_row(const uchar * buf);
   int update_row(const uchar * old_data, const uchar * new_data);
   int delete_row(const uchar * buf);
   int index_read_map(uchar * buf, const uchar * key, key_part_map keypart_map,
diff --git a/storage/maria/ma_write.c b/storage/maria/ma_write.c
index faf47929973..07be8333794 100644
--- a/storage/maria/ma_write.c
+++ b/storage/maria/ma_write.c
@@ -83,7 +83,7 @@ my_bool _ma_write_abort_default(MARIA_HA *info __attribute__((unused)))
 
 /* Write new record to a table */
 
-int maria_write(MARIA_HA *info, uchar *record)
+int maria_write(MARIA_HA *info, const uchar *record)
 {
   MARIA_SHARE *share= info->s;
   uint i;
diff --git a/storage/mroonga/ha_mroonga.cpp b/storage/mroonga/ha_mroonga.cpp
index a2ab9dd6423..767f357c9fe 100644
--- a/storage/mroonga/ha_mroonga.cpp
+++ b/storage/mroonga/ha_mroonga.cpp
@@ -5852,7 +5852,7 @@ bool ha_mroonga::wrapper_have_target_index()
   DBUG_RETURN(have_target_index);
 }
 
-int ha_mroonga::wrapper_write_row(uchar *buf)
+int ha_mroonga::wrapper_write_row(const uchar *buf)
 {
   int error = 0;
   THD *thd = ha_thd();
@@ -5881,7 +5881,7 @@ int ha_mroonga::wrapper_write_row(uchar *buf)
   DBUG_RETURN(error);
 }
 
-int ha_mroonga::wrapper_write_row_index(uchar *buf)
+int ha_mroonga::wrapper_write_row_index(const uchar *buf)
 {
   MRN_DBUG_ENTER_METHOD();
 
@@ -5968,7 +5968,7 @@ err:
   DBUG_RETURN(error);
 }
 
-int ha_mroonga::storage_write_row(uchar *buf)
+int ha_mroonga::storage_write_row(const uchar *buf)
 {
   MRN_DBUG_ENTER_METHOD();
   int error = 0;
@@ -6231,7 +6231,7 @@ err:
   DBUG_RETURN(error);
 }
 
-int ha_mroonga::storage_write_row_multiple_column_index(uchar *buf,
+int ha_mroonga::storage_write_row_multiple_column_index(const uchar *buf,
                                                         grn_id record_id,
                                                         KEY *key_info,
                                                         grn_obj *index_column)
@@ -6268,7 +6268,7 @@ int ha_mroonga::storage_write_row_multiple_column_index(uchar *buf,
   DBUG_RETURN(error);
 }
 
-int ha_mroonga::storage_write_row_multiple_column_indexes(uchar *buf,
+int ha_mroonga::storage_write_row_multiple_column_indexes(const uchar *buf,
                                                           grn_id record_id)
 {
   MRN_DBUG_ENTER_METHOD();
@@ -6380,7 +6380,7 @@ int ha_mroonga::storage_write_row_unique_index(const uchar *buf,
   DBUG_RETURN(0);
 }
 
-int ha_mroonga::storage_write_row_unique_indexes(uchar *buf)
+int ha_mroonga::storage_write_row_unique_indexes(const uchar *buf)
 {
   int error = 0;
   uint i;
@@ -6443,7 +6443,7 @@ err:
   DBUG_RETURN(error);
 }
 
-int ha_mroonga::write_row(uchar *buf)
+int ha_mroonga::write_row(const uchar *buf)
 {
   MRN_DBUG_ENTER_METHOD();
   int error = 0;
diff --git a/storage/mroonga/ha_mroonga.hpp b/storage/mroonga/ha_mroonga.hpp
index 4c64959b17f..9b545450185 100644
--- a/storage/mroonga/ha_mroonga.hpp
+++ b/storage/mroonga/ha_mroonga.hpp
@@ -451,7 +451,7 @@ public:
   int extra_opt(enum ha_extra_function operation, ulong cache_size);
 
   int delete_table(const char *name);
-  int write_row(uchar *buf);
+  int write_row(const uchar *buf);
   int update_row(const uchar *old_data, const uchar *new_data);
   int delete_row(const uchar *buf);
 
@@ -908,20 +908,20 @@ private:
   int storage_end_bulk_insert();
   bool wrapper_is_target_index(KEY *key_info);
   bool wrapper_have_target_index();
-  int wrapper_write_row(uchar *buf);
-  int wrapper_write_row_index(uchar *buf);
-  int storage_write_row(uchar *buf);
-  int storage_write_row_multiple_column_index(uchar *buf,
+  int wrapper_write_row(const uchar *buf);
+  int wrapper_write_row_index(const uchar *buf);
+  int storage_write_row(const uchar *buf);
+  int storage_write_row_multiple_column_index(const uchar *buf,
                                               grn_id record_id,
                                               KEY *key_info,
                                               grn_obj *index_column);
-  int storage_write_row_multiple_column_indexes(uchar *buf, grn_id record_id);
+  int storage_write_row_multiple_column_indexes(const uchar *buf, grn_id record_id);
   int storage_write_row_unique_index(const uchar *buf,
                                      KEY *key_info,
                                      grn_obj *index_table,
                                      grn_obj *index_column,
                                      grn_id *key_id);
-  int storage_write_row_unique_indexes(uchar *buf);
+  int storage_write_row_unique_indexes(const uchar *buf);
   int wrapper_get_record_id(uchar *data, grn_id *record_id,
                             const char *context);
   int wrapper_update_row(const uchar *old_data, const uchar *new_data);
diff --git a/storage/myisam/ha_myisam.cc b/storage/myisam/ha_myisam.cc
index 19382ee4a50..f478e01e441 100644
--- a/storage/myisam/ha_myisam.cc
+++ b/storage/myisam/ha_myisam.cc
@@ -933,7 +933,7 @@ int ha_myisam::close(void)
   return mi_close(tmp);
 }
 
-int ha_myisam::write_row(uchar *buf)
+int ha_myisam::write_row(const uchar *buf)
 {
   /*
     If we have an auto_increment column and we are writing a changed row
diff --git a/storage/myisam/ha_myisam.h b/storage/myisam/ha_myisam.h
index 3e191ecfa3f..0af4215e8f9 100644
--- a/storage/myisam/ha_myisam.h
+++ b/storage/myisam/ha_myisam.h
@@ -69,7 +69,7 @@ class ha_myisam: public handler
   void change_table_ptr(TABLE *table_arg, TABLE_SHARE *share);
   int open(const char *name, int mode, uint test_if_locked);
   int close(void);
-  int write_row(uchar * buf);
+  int write_row(const uchar * buf);
   int update_row(const uchar * old_data, const uchar * new_data);
   int delete_row(const uchar * buf);
   int index_read_map(uchar *buf, const uchar *key, key_part_map keypart_map,
diff --git a/storage/myisam/mi_write.c b/storage/myisam/mi_write.c
index f08dea77354..7345ab1604d 100644
--- a/storage/myisam/mi_write.c
+++ b/storage/myisam/mi_write.c
@@ -40,7 +40,7 @@ int _mi_ck_write_btree(register MI_INFO *info, uint keynr,uchar *key,
 
 	/* Write new record to database */
 
-int mi_write(MI_INFO *info, uchar *record)
+int mi_write(MI_INFO *info, const uchar *record)
 {
   MYISAM_SHARE *share=info->s;
   uint i;
diff --git a/storage/myisammrg/ha_myisammrg.cc b/storage/myisammrg/ha_myisammrg.cc
index 8f5e65084ce..14036a31b8c 100644
--- a/storage/myisammrg/ha_myisammrg.cc
+++ b/storage/myisammrg/ha_myisammrg.cc
@@ -1088,7 +1088,7 @@ int ha_myisammrg::close(void)
   DBUG_RETURN(rc);
 }
 
-int ha_myisammrg::write_row(uchar * buf)
+int ha_myisammrg::write_row(const uchar * buf)
 {
   DBUG_ENTER("ha_myisammrg::write_row");
   DBUG_ASSERT(this->file->children_attached);
diff --git a/storage/myisammrg/ha_myisammrg.h b/storage/myisammrg/ha_myisammrg.h
index 7cb2b0f1993..b7cbd6c7d12 100644
--- a/storage/myisammrg/ha_myisammrg.h
+++ b/storage/myisammrg/ha_myisammrg.h
@@ -111,7 +111,7 @@ public:
   int detach_children(void);
   virtual handler *clone(const char *name, MEM_ROOT *mem_root);
   int close(void);
-  int write_row(uchar * buf);
+  int write_row(const uchar * buf);
   int update_row(const uchar * old_data, const uchar * new_data);
   int delete_row(const uchar * buf);
   int index_read_map(uchar *buf, const uchar *key, key_part_map keypart_map,
diff --git a/storage/myisammrg/myrg_write.c b/storage/myisammrg/myrg_write.c
index eb496911a52..e511d60d634 100644
--- a/storage/myisammrg/myrg_write.c
+++ b/storage/myisammrg/myrg_write.c
@@ -18,7 +18,7 @@
 
 #include "myrg_def.h"
 
-int myrg_write(register MYRG_INFO *info, uchar *rec)
+int myrg_write(register MYRG_INFO *info, const uchar *rec)
 {
   /* [phi] MERGE_WRITE_DISABLED is handled by the else case */
   if (info->merge_insert_method == MERGE_INSERT_TO_FIRST)
diff --git a/storage/oqgraph/ha_oqgraph.cc b/storage/oqgraph/ha_oqgraph.cc
index 4154f89028a..fd715c57a1f 100644
--- a/storage/oqgraph/ha_oqgraph.cc
+++ b/storage/oqgraph/ha_oqgraph.cc
@@ -799,7 +799,7 @@ void ha_oqgraph::update_key_stats()
 }
 
 
-int ha_oqgraph::write_row(byte * buf)
+int ha_oqgraph::write_row(const byte * buf)
 {
   return HA_ERR_TABLE_READONLY;
 }
diff --git a/storage/oqgraph/ha_oqgraph.h b/storage/oqgraph/ha_oqgraph.h
index d0ac8d7e18c..0c0af6def97 100644
--- a/storage/oqgraph/ha_oqgraph.h
+++ b/storage/oqgraph/ha_oqgraph.h
@@ -83,7 +83,7 @@ public:
 
   int open(const char *name, int mode, uint test_if_locked);
   int close(void);
-  int write_row(byte * buf);
+  int write_row(const byte * buf);
   int update_row(const uchar * old_data, const uchar * new_data);
   int delete_row(const byte * buf);
   int index_read(byte * buf, const byte * key,
diff --git a/storage/perfschema/ha_perfschema.cc b/storage/perfschema/ha_perfschema.cc
index cb5805db5da..50d7a3aa468 100644
--- a/storage/perfschema/ha_perfschema.cc
+++ b/storage/perfschema/ha_perfschema.cc
@@ -251,7 +251,7 @@ int ha_perfschema::close(void)
   DBUG_RETURN(0);
 }
 
-int ha_perfschema::write_row(uchar *buf)
+int ha_perfschema::write_row(const uchar *buf)
 {
   int result;
 
diff --git a/storage/perfschema/ha_perfschema.h b/storage/perfschema/ha_perfschema.h
index 4aad6a3beef..31b4e84e87d 100644
--- a/storage/perfschema/ha_perfschema.h
+++ b/storage/perfschema/ha_perfschema.h
@@ -120,7 +120,7 @@ public:
     @param buf the row to write
     @return 0 on success
   */
-  int write_row(uchar *buf);
+  int write_row(const uchar *buf);
 
   void use_hidden_primary_key();
 
diff --git a/storage/perfschema/pfs_engine_table.cc b/storage/perfschema/pfs_engine_table.cc
index b133988e908..380818cf025 100644
--- a/storage/perfschema/pfs_engine_table.cc
+++ b/storage/perfschema/pfs_engine_table.cc
@@ -178,7 +178,7 @@ ha_rows PFS_engine_table_share::get_row_count(void) const
   return m_records;
 }
 
-int PFS_engine_table_share::write_row(TABLE *table, unsigned char *buf,
+int PFS_engine_table_share::write_row(TABLE *table, const unsigned char *buf,
                                       Field **fields) const
 {
   my_bitmap_map *org_bitmap;
diff --git a/storage/perfschema/pfs_engine_table.h b/storage/perfschema/pfs_engine_table.h
index b29a9c54754..d58ac4390f9 100644
--- a/storage/perfschema/pfs_engine_table.h
+++ b/storage/perfschema/pfs_engine_table.h
@@ -200,7 +200,7 @@ protected:
 typedef PFS_engine_table* (*pfs_open_table_t)(void);
 /** Callback to write a row. */
 typedef int (*pfs_write_row_t)(TABLE *table,
-                               unsigned char *buf, Field **fields);
+                               const unsigned char *buf, Field **fields);
 /** Callback to delete all rows. */
 typedef int (*pfs_delete_all_rows_t)(void);
 /** Callback to get a row count. */
@@ -217,7 +217,7 @@ struct PFS_engine_table_share
   /** Get the row count. */
   ha_rows get_row_count(void) const;
   /** Write a row. */
-  int write_row(TABLE *table, unsigned char *buf, Field **fields) const;
+  int write_row(TABLE *table, const unsigned char *buf, Field **fields) const;
 
   /** Table name. */
   LEX_STRING m_name;
diff --git a/storage/perfschema/table_setup_actors.cc b/storage/perfschema/table_setup_actors.cc
index b5058f8cd85..1ff1ac8c412 100644
--- a/storage/perfschema/table_setup_actors.cc
+++ b/storage/perfschema/table_setup_actors.cc
@@ -52,7 +52,7 @@ PFS_engine_table* table_setup_actors::create()
   return new table_setup_actors();
 }
 
-int table_setup_actors::write_row(TABLE *table, unsigned char *buf,
+int table_setup_actors::write_row(TABLE *table, const unsigned char *buf,
                                   Field **fields)
 {
   Field *f;
diff --git a/storage/perfschema/table_setup_actors.h b/storage/perfschema/table_setup_actors.h
index aa403b4909d..2e274a0cf15 100644
--- a/storage/perfschema/table_setup_actors.h
+++ b/storage/perfschema/table_setup_actors.h
@@ -55,7 +55,7 @@ public:
   static PFS_engine_table_share m_share;
   /** Table builder. */
   static PFS_engine_table* create();
-  static int write_row(TABLE *table, unsigned char *buf, Field **fields);
+  static int write_row(TABLE *table, const unsigned char *buf, Field **fields);
   static int delete_all_rows();
   static ha_rows get_row_count();
 
diff --git a/storage/perfschema/table_setup_objects.cc b/storage/perfschema/table_setup_objects.cc
index e15c55b41ae..c3f3e01f933 100644
--- a/storage/perfschema/table_setup_objects.cc
+++ b/storage/perfschema/table_setup_objects.cc
@@ -66,7 +66,7 @@ PFS_engine_table* table_setup_objects::create(void)
   return new table_setup_objects();
 }
 
-int table_setup_objects::write_row(TABLE *table, unsigned char *buf,
+int table_setup_objects::write_row(TABLE *table, const unsigned char *buf,
                                    Field **fields)
 {
   int result;
diff --git a/storage/perfschema/table_setup_objects.h b/storage/perfschema/table_setup_objects.h
index 8e883126298..d8fd041bd57 100644
--- a/storage/perfschema/table_setup_objects.h
+++ b/storage/perfschema/table_setup_objects.h
@@ -58,7 +58,7 @@ public:
   static PFS_engine_table_share m_share;
   /** Table builder. */
   static PFS_engine_table* create();
-  static int write_row(TABLE *table, unsigned char *buf, Field **fields);
+  static int write_row(TABLE *table, const unsigned char *buf, Field **fields);
   static int delete_all_rows();
   static ha_rows get_row_count();
 
diff --git a/storage/rocksdb/ha_rocksdb.cc b/storage/rocksdb/ha_rocksdb.cc
index 5300f84db1e..59c764caa96 100644
--- a/storage/rocksdb/ha_rocksdb.cc
+++ b/storage/rocksdb/ha_rocksdb.cc
@@ -9485,7 +9485,7 @@ const std::string ha_rocksdb::get_table_comment(const TABLE *const table_arg) {
     HA_EXIT_SUCCESS  OK
     other            HA_ERR error code (can be SE-specific)
 */
-int ha_rocksdb::write_row(uchar *const buf) {
+int ha_rocksdb::write_row(const uchar *const buf) {
   DBUG_ENTER_FUNC();
 
   DBUG_ASSERT(buf != nullptr);
diff --git a/storage/rocksdb/ha_rocksdb.h b/storage/rocksdb/ha_rocksdb.h
index cadbd9abfe9..1abdc345527 100644
--- a/storage/rocksdb/ha_rocksdb.h
+++ b/storage/rocksdb/ha_rocksdb.h
@@ -640,7 +640,7 @@ public:
       MY_ATTRIBUTE((__warn_unused_result__));
   int close(void) override MY_ATTRIBUTE((__warn_unused_result__));
 
-  int write_row(uchar *const buf) override
+  int write_row(const uchar *const buf) override
       MY_ATTRIBUTE((__warn_unused_result__));
   int update_row(const uchar *const old_data, const uchar *const new_data) override
       MY_ATTRIBUTE((__warn_unused_result__));
diff --git a/storage/spider/ha_spider.cc b/storage/spider/ha_spider.cc
index 33e81201fff..5457bc0ba50 100644
--- a/storage/spider/ha_spider.cc
+++ b/storage/spider/ha_spider.cc
@@ -9796,7 +9796,7 @@ int ha_spider::end_bulk_insert()
 }
 
 int ha_spider::write_row(
-  uchar *buf
+  const uchar *buf
 ) {
   int error_num;
   THD *thd = ha_thd();
diff --git a/storage/spider/ha_spider.h b/storage/spider/ha_spider.h
index 6f5359007f1..a146745aa97 100644
--- a/storage/spider/ha_spider.h
+++ b/storage/spider/ha_spider.h
@@ -568,7 +568,7 @@ public:
 #endif
   int end_bulk_insert();
   int write_row(
-    uchar *buf
+    const uchar *buf
   );
 #ifdef HA_CAN_BULK_ACCESS
   int pre_write_row(
diff --git a/storage/tokudb/ha_tokudb.cc b/storage/tokudb/ha_tokudb.cc
index 2be8556a123..c19a75d680d 100644
--- a/storage/tokudb/ha_tokudb.cc
+++ b/storage/tokudb/ha_tokudb.cc
@@ -3714,7 +3714,7 @@ static bool do_unique_checks_fn(THD *thd) {
 
 #endif // defined(TOKU_INCLUDE_RFR) && TOKU_INCLUDE_RFR
 
-int ha_tokudb::do_uniqueness_checks(uchar* record, DB_TXN* txn, THD* thd) {
+int ha_tokudb::do_uniqueness_checks(const uchar* record, DB_TXN* txn, THD* thd) {
     int error = 0;
     //
     // first do uniqueness checks
@@ -3757,7 +3757,7 @@ cleanup:
     return error;
 }
 
-void ha_tokudb::test_row_packing(uchar* record, DBT* pk_key, DBT* pk_val) {
+void ha_tokudb::test_row_packing(const uchar* record, DBT* pk_key, DBT* pk_val) {
     int error;
     DBT row, key;
     //
@@ -3998,7 +3998,7 @@ out:
 //      0 on success
 //      error otherwise
 //
-int ha_tokudb::write_row(uchar * record) {
+int ha_tokudb::write_row(const uchar * record) {
     TOKUDB_HANDLER_DBUG_ENTER("%p", record);
 
     DBT row, prim_key;
diff --git a/storage/tokudb/ha_tokudb.h b/storage/tokudb/ha_tokudb.h
index c36c93a4c74..f95143a6b4b 100644
--- a/storage/tokudb/ha_tokudb.h
+++ b/storage/tokudb/ha_tokudb.h
@@ -703,11 +703,11 @@ private:
     void trace_create_table_info(TABLE* form);
     int is_index_unique(bool* is_unique, DB_TXN* txn, DB* db, KEY* key_info, int lock_flags);
     int is_val_unique(bool* is_unique, const uchar* record, KEY* key_info, uint dict_index, DB_TXN* txn);
-    int do_uniqueness_checks(uchar* record, DB_TXN* txn, THD* thd);
+    int do_uniqueness_checks(const uchar* record, DB_TXN* txn, THD* thd);
     void set_main_dict_put_flags(THD* thd, bool opt_eligible, uint32_t* put_flags);
     int insert_row_to_main_dictionary(DBT* pk_key, DBT* pk_val, DB_TXN* txn);
     int insert_rows_to_dictionaries_mult(DBT* pk_key, DBT* pk_val, DB_TXN* txn, THD* thd);
-    void test_row_packing(uchar* record, DBT* pk_key, DBT* pk_val);
+    void test_row_packing(const uchar* record, DBT* pk_key, DBT* pk_val);
     uint32_t fill_row_mutator(
         uchar* buf, 
         uint32_t* dropped_columns, 
@@ -785,7 +785,7 @@ public:
     int rename_table(const char *from, const char *to);
     int optimize(THD * thd, HA_CHECK_OPT * check_opt);
     int analyze(THD * thd, HA_CHECK_OPT * check_opt);
-    int write_row(uchar * buf);
+    int write_row(const uchar * buf);
     int update_row(const uchar * old_data, const uchar * new_data);
     int delete_row(const uchar * buf);
 #if MYSQL_VERSION_ID >= 100000