MDEV-13654 Various crashes due to DB_TRX_ID mismatch in table-rebuilding ALTER TABLE…LOCK=NONE

After MDEV-12288 and MDEV-13536, the DB_TRX_ID of old clustered index
records for which no history is available should be reset to 0.

This caused crashes in online table-rebuilding ALTER, because the
row_log_table_apply() is built on the assumption that the PRIMARY KEY
together with DB_TRX_ID,DB_ROLL_PTR identifies the record.

Both when copying the old table and when writing log about changes to
the old table, we must map "old" DB_TRX_ID to 0. "old" here is simply
"older than the trx_id of the ALTER TABLE transaction", because
the MDL_EXCLUSIVE (and exclusive InnoDB table lock) in
ha_innobase::prepare_inplace_alter_table() forces any transactions
accessing the table to commit or rollback. So, we know that we can
safely reset any DB_TRX_ID in the table that is older than the
transaction ID of the ALTER TABLE, because the undo log history would be
lost in a table-rebuilding ALTER.

Note: After a table-rebuilding online ALTER TABLE, the rebuilt table
may end up containing some nonzero DB_TRX_ID columns. The apply logic
identifies the rows by the combination of PRIMARY KEY and DB_TRX_ID.
These nonzero DB_TRX_ID would necessarily refer to concurrent DML
operations that were started during ha_innobase::inplace_alter_table().

row_log_allocate(): Add a parameter for the ALTER TABLE transaction.

row_log_t::min_trx: The ALTER TABLE transaction ID.

trx_id_check(): A debug function to check that DB_TRX_ID makes sense
(is either 0 or bigger than the ALTER TABLE transaction ID).

reset_trx_id[]: The reset DB_TRX_ID,DB_ROLL_PTR columns.

row_log_table_delete(), row_log_table_get_pk(): Reset the
DB_TRX_ID,DB_ROLL_PTR when they precede the ALTER TABLE transaction.

row_log_table_apply_delete(), row_log_table_apply_update():
Assert trx_id_check().

row_merge_insert_index_tuples(): Remove the unused parameter trx_id.

row_merge_read_clustered_index(): In a table-rebuilding ALTER,
reset the DB_TRX_ID,DB_ROLL_PTR when they precede the ALTER TABLE
transaction. Assert trx_id_check() on clustered index records that
are being buffered.

storage/innobase/handler/handler0alter.cc

@@ -4911,7 +4911,8 @@ prepare_inplace_alter_table_dict(
 					goto error_handling;);
 			rw_lock_x_lock(&ctx->add_index[a]->lock);
 
-			bool ok = row_log_allocate(ctx->add_index[a],
+			bool ok = row_log_allocate(ctx->prebuilt->trx,
+						   ctx->add_index[a],
 						   NULL, true, NULL, NULL,
 						   path);
 			rw_lock_x_unlock(&ctx->add_index[a]->lock);
@@ -4961,6 +4962,7 @@ prepare_inplace_alter_table_dict(
 			/* Allocate a log for online table rebuild. */
 			rw_lock_x_lock(&clust_index->lock);
 			bool ok = row_log_allocate(
+				ctx->prebuilt->trx,
 				clust_index, ctx->new_table,
 				!(ha_alter_info->handler_flags
 				  & Alter_inplace_info::ADD_PK_INDEX),

storage/innobase/include/row0log.h

@@ -48,6 +48,7 @@ for online creation.
 bool
 row_log_allocate(
 /*=============*/
+	const trx_t*	trx,	/*!< in: the ALTER TABLE transaction */
 	dict_index_t*	index,	/*!< in/out: index */
 	dict_table_t*	table,	/*!< in/out: new table being rebuilt,
 				or NULL when creating a secondary index */

storage/innobase/include/trx0sys.h

@@ -163,16 +163,31 @@ trx_write_trx_id(
 /*=============*/
 	byte*		ptr,	/*!< in: pointer to memory where written */
 	trx_id_t	id);	/*!< in: id */
-/*****************************************************************//**
-Reads a trx id from an index page. In case that the id size changes in
-some future version, this function should be used instead of
-mach_read_...
+
+/** Read a transaction identifier.
 @return id */
-UNIV_INLINE
+inline
 trx_id_t
-trx_read_trx_id(
-/*============*/
-	const byte*	ptr);	/*!< in: pointer to memory from where to read */
+trx_read_trx_id(const byte* ptr)
+{
+#if DATA_TRX_ID_LEN != 6
+# error "DATA_TRX_ID_LEN != 6"
+#endif
+	return(mach_read_from_6(ptr));
+}
+
+#ifdef UNIV_DEBUG
+/** Check that the DB_TRX_ID in a record is valid.
+@param[in]	db_trx_id	the DB_TRX_ID column to validate
+@param[in]	trx_id		the id of the ALTER TABLE transaction */
+inline bool trx_id_check(const void* db_trx_id, trx_id_t trx_id)
+{
+	trx_id_t id = trx_read_trx_id(static_cast<const byte*>(db_trx_id));
+	ut_ad(id == 0 || id > trx_id);
+	return true;
+}
+#endif
+
 /****************************************************************//**
 Looks for the trx instance with the given id in the rw trx_list.
 @return	the trx handle or NULL if not found */

storage/innobase/include/trx0sys.ic

@@ -191,23 +191,6 @@ trx_write_trx_id(
 	mach_write_to_6(ptr, id);
 }
 
-/*****************************************************************//**
-Reads a trx id from an index page. In case that the id size changes in
-some future version, this function should be used instead of
-mach_read_...
-@return id */
-UNIV_INLINE
-trx_id_t
-trx_read_trx_id(
-/*============*/
-	const byte*	ptr)	/*!< in: pointer to memory from where to read */
-{
-#if DATA_TRX_ID_LEN != 6
-# error "DATA_TRX_ID_LEN != 6"
-#endif
-	return(mach_read_from_6(ptr));
-}
-
 /****************************************************************//**
 Looks for the trx handle with the given id in rw_trx_list.
 The caller must be holding trx_sys->mutex.

storage/innobase/row/row0log.cc

@@ -45,6 +45,12 @@ ulint onlineddl_rowlog_rows;
 ulint onlineddl_rowlog_pct_used;
 ulint onlineddl_pct_progress;
 
+/** The DB_TRX_ID,DB_ROLL_PTR values for "no history is available" */
+static const byte reset_trx_id[DATA_TRX_ID_LEN + DATA_ROLL_PTR_LEN] = {
+	0, 0, 0, 0, 0, 0,
+	0x80, 0, 0, 0, 0, 0, 0
+};
+
 /** Table row modification operations during online table rebuild.
 Delete-marked records are not copied to the rebuilt table. */
 enum row_tab_op {
@@ -187,6 +193,20 @@ struct row_log_t {
 				new ones, or NULL if !table */
 	dberr_t		error;	/*!< error that occurred during online
 				table rebuild */
+	/** The transaction ID of the ALTER TABLE transaction.  Any
+	concurrent DML would necessarily be logged with a larger
+	transaction ID, because ha_innobase::prepare_inplace_alter_table()
+	acts as a barrier that ensures that any concurrent transaction
+	that operates on the table would have been started after
+	ha_innobase::prepare_inplace_alter_table() returns and before
+	ha_innobase::commit_inplace_alter_table(commit=true) is invoked.
+
+	Due to the nondeterministic nature of purge and due to the
+	possibility of upgrading from an earlier version of MariaDB
+	or MySQL, it is possible that row_log_table_low() would be
+	fed DB_TRX_ID that precedes than min_trx. We must normalize
+	such references to reset_trx_id[]. */
+	trx_id_t	min_trx;
 	trx_id_t	max_trx;/*!< biggest observed trx_id in
 				row_log_online_op();
 				protected by mutex and index->lock S-latch,
@@ -586,6 +606,7 @@ row_log_table_delete(
 
 	ut_ad(dict_index_is_clust(new_index));
 	ut_ad(!dict_index_is_online_ddl(new_index));
+	ut_ad(index->online_log->min_trx);
 
 	/* Create the tuple PRIMARY KEY,DB_TRX_ID,DB_ROLL_PTR in new_table. */
 	if (index->online_log->same_pk) {
@@ -612,16 +633,27 @@ row_log_table_delete(
 			dfield_set_data(dfield, field, len);
 		}
 
-		if (sys) {
-			dfield_set_data(
-				dtuple_get_nth_field(tuple,
-						     new_index->n_uniq),
-				sys, DATA_TRX_ID_LEN);
-			dfield_set_data(
-				dtuple_get_nth_field(tuple,
-						     new_index->n_uniq + 1),
-				sys + DATA_TRX_ID_LEN, DATA_ROLL_PTR_LEN);
+		dfield_t* db_trx_id = dtuple_get_nth_field(
+			tuple, new_index->n_uniq);
+
+		const bool replace_sys_fields
+			= sys
+			|| trx_read_trx_id(static_cast<byte*>(db_trx_id->data))
+			< index->online_log->min_trx;
+
+		if (replace_sys_fields) {
+			if (!sys || trx_read_trx_id(sys)
+			    < index->online_log->min_trx) {
+				sys = reset_trx_id;
+			}
+
+			dfield_set_data(db_trx_id, sys, DATA_TRX_ID_LEN);
+			dfield_set_data(db_trx_id + 1, sys + DATA_TRX_ID_LEN,
+					DATA_ROLL_PTR_LEN);
 		}
+
+		ut_d(trx_id_check(db_trx_id->data,
+				  index->online_log->min_trx));
 	} else {
 		/* The PRIMARY KEY has changed. Translate the tuple. */
 		old_pk = row_log_table_get_pk(
@@ -1184,6 +1216,7 @@ row_log_table_get_pk(
 
 	ut_ad(log);
 	ut_ad(log->table);
+	ut_ad(log->min_trx);
 
 	if (log->same_pk) {
 		/* The PRIMARY KEY columns are unchanged. */
@@ -1208,8 +1241,13 @@ row_log_table_get_pk(
 				ut_ad(len == DATA_TRX_ID_LEN);
 			}
 
-			memcpy(sys, rec + trx_id_offs,
-			       DATA_TRX_ID_LEN + DATA_ROLL_PTR_LEN);
+			const byte* ptr = trx_read_trx_id(rec + trx_id_offs)
+				< log->min_trx
+				? reset_trx_id
+				: rec + trx_id_offs;
+
+			memcpy(sys, ptr, DATA_TRX_ID_LEN + DATA_ROLL_PTR_LEN);
+			ut_d(trx_id_check(sys, log->min_trx));
 		}
 
 		return(NULL);
@@ -1326,7 +1364,13 @@ row_log_table_get_pk(
 		/* Copy the fields, because the fields will be updated
 		or the record may be moved somewhere else in the B-tree
 		as part of the upcoming operation. */
-		if (sys) {
+		if (trx_read_trx_id(trx_roll) < log->min_trx) {
+			trx_roll = reset_trx_id;
+			if (sys) {
+				memcpy(sys, trx_roll,
+				       DATA_TRX_ID_LEN + DATA_ROLL_PTR_LEN);
+			}
+		} else if (sys) {
 			memcpy(sys, trx_roll,
 			       DATA_TRX_ID_LEN + DATA_ROLL_PTR_LEN);
 			trx_roll = sys;
@@ -1337,6 +1381,8 @@ row_log_table_get_pk(
 					DATA_TRX_ID_LEN + DATA_ROLL_PTR_LEN));
 		}
 
+		ut_d(trx_id_check(trx_roll, log->min_trx));
+
 		dfield_set_data(dtuple_get_nth_field(tuple, new_n_uniq),
 				trx_roll, DATA_TRX_ID_LEN);
 		dfield_set_data(dtuple_get_nth_field(tuple, new_n_uniq + 1),
@@ -1938,6 +1984,8 @@ row_log_table_apply_delete(
 			= rec_get_nth_field(btr_pcur_get_rec(&pcur), offsets,
 					    trx_id_col, &len);
 		ut_ad(len == DATA_TRX_ID_LEN);
+		ut_d(trx_id_check(rec_trx_id, log->min_trx));
+		ut_d(trx_id_check(mrec_trx_id, log->min_trx));
 
 		ut_ad(rec_get_nth_field(mrec, moffsets, trx_id_col + 1, &len)
 		      == mrec_trx_id + DATA_TRX_ID_LEN);
@@ -2132,21 +2180,21 @@ row_log_table_apply_update(
 		/* Only update the record if DB_TRX_ID,DB_ROLL_PTR match what
 		was buffered. */
 		ulint		len;
-		const void*	rec_trx_id
+		const byte*	rec_trx_id
 			= rec_get_nth_field(btr_pcur_get_rec(&pcur),
 					    cur_offsets, index->n_uniq, &len);
+		const dfield_t*	old_pk_trx_id
+			= dtuple_get_nth_field(old_pk, index->n_uniq);
 		ut_ad(len == DATA_TRX_ID_LEN);
-		ut_ad(dtuple_get_nth_field(old_pk, index->n_uniq)->len
-		      == DATA_TRX_ID_LEN);
-		ut_ad(dtuple_get_nth_field(old_pk, index->n_uniq + 1)->len
-		      == DATA_ROLL_PTR_LEN);
-		ut_ad(DATA_TRX_ID_LEN + static_cast<const char*>(
-			      dtuple_get_nth_field(old_pk,
-						   index->n_uniq)->data)
-		      == dtuple_get_nth_field(old_pk,
-					      index->n_uniq + 1)->data);
-		if (memcmp(rec_trx_id,
-			   dtuple_get_nth_field(old_pk, index->n_uniq)->data,
+		ut_d(trx_id_check(rec_trx_id, log->min_trx));
+		ut_ad(old_pk_trx_id->len == DATA_TRX_ID_LEN);
+		ut_ad(old_pk_trx_id[1].len == DATA_ROLL_PTR_LEN);
+		ut_ad(DATA_TRX_ID_LEN
+		      + static_cast<const char*>(old_pk_trx_id->data)
+		      == old_pk_trx_id[1].data);
+		ut_d(trx_id_check(old_pk_trx_id->data, log->min_trx));
+
+		if (memcmp(rec_trx_id, old_pk_trx_id->data,
 			   DATA_TRX_ID_LEN + DATA_ROLL_PTR_LEN)) {
 			/* The ROW_T_UPDATE was logged for a different
 			DB_TRX_ID,DB_ROLL_PTR. This is possible if an
@@ -3132,6 +3180,7 @@ for online creation.
 bool
 row_log_allocate(
 /*=============*/
+	const trx_t*	trx,	/*!< in: the ALTER TABLE transaction */
 	dict_index_t*	index,	/*!< in/out: index */
 	dict_table_t*	table,	/*!< in/out: new table being rebuilt,
 				or NULL when creating a secondary index */
@@ -3154,6 +3203,8 @@ row_log_allocate(
 	ut_ad(!table || col_map);
 	ut_ad(!add_cols || col_map);
 	ut_ad(rw_lock_own(dict_index_get_lock(index), RW_LOCK_X));
+	ut_ad(trx_state_eq(trx, TRX_STATE_ACTIVE));
+	ut_ad(trx->id);
 
 	log = static_cast<row_log_t*>(ut_malloc_nokey(sizeof *log));
 
@@ -3170,6 +3221,7 @@ row_log_allocate(
 	log->add_cols = add_cols;
 	log->col_map = col_map;
 	log->error = DB_SUCCESS;
+	log->min_trx = trx->id;
 	log->max_trx = 0;
 	log->tail.blocks = log->tail.bytes = 0;
 	log->tail.total = 0;

storage/innobase/row/row0merge.cc

@@ -357,7 +357,6 @@ row_merge_decrypt_buf(
 #define FTS_PENDING_DOC_MEMORY_LIMIT	1000000
 
 /** Insert sorted data tuples to the index.
-@param[in]	trx_id		transaction identifier
 @param[in]	index		index to be inserted
 @param[in]	old_table	old table
 @param[in]	fd		file descriptor
@@ -372,7 +371,6 @@ and then stage->inc() will be called for each record that is processed.
 static	MY_ATTRIBUTE((warn_unused_result))
 dberr_t
 row_merge_insert_index_tuples(
-	trx_id_t		trx_id,
 	dict_index_t*		index,
 	const dict_table_t*	old_table,
 	int			fd,
@@ -1832,6 +1830,8 @@ row_merge_read_clustered_index(
 
 	ut_ad((old_table == new_table) == !col_map);
 	ut_ad(!add_cols || col_map);
+	ut_ad(trx_state_eq(trx, TRX_STATE_ACTIVE));
+	ut_ad(trx->id);
 
 	table_total_rows = dict_table_get_n_rows(old_table);
 	if(table_total_rows == 0) {
@@ -1927,6 +1927,16 @@ row_merge_read_clustered_index(
 	based on that. */
 
 	clust_index = dict_table_get_first_index(old_table);
+	const ulint old_trx_id_col = old_table->n_cols + DATA_TRX_ID
+		- dict_table_get_n_sys_cols(table);
+	ut_ad(old_table->cols[old_trx_id_col].mtype == DATA_SYS);
+	ut_ad(old_table->cols[old_trx_id_col].prtype
+	      == (DATA_TRX_ID | DATA_NOT_NULL));
+	ut_ad(old_table->cols[old_trx_id_col + 1].mtype == DATA_SYS);
+	ut_ad(old_table->cols[old_trx_id_col + 1].prtype
+	      == (DATA_ROLL_PTR | DATA_NOT_NULL));
+	const ulint new_trx_id_col = col_map
+		? col_map[old_trx_id_col] : old_trx_id_col;
 
 	btr_pcur_open_at_index_side(
 		true, clust_index, BTR_SEARCH_LEAF, &pcur, true, 0, &mtr);
@@ -1984,6 +1994,7 @@ row_merge_read_clustered_index(
 	/* Scan the clustered index. */
 	for (;;) {
 		const rec_t*	rec;
+		trx_id_t	rec_trx_id;
 		ulint*		offsets;
 		const dtuple_t*	row;
 		row_ext_t*	ext;
@@ -2135,6 +2146,8 @@ row_merge_read_clustered_index(
 		if (online) {
 			offsets = rec_get_offsets(rec, clust_index, NULL,
 						  ULINT_UNDEFINED, &row_heap);
+			rec_trx_id = row_get_rec_trx_id(rec, clust_index,
+							offsets);
 
 			/* Perform a REPEATABLE READ.
 
@@ -2156,11 +2169,10 @@ row_merge_read_clustered_index(
 			the DML thread has updated the clustered index
 			but has not yet accessed secondary index. */
 			ut_ad(MVCC::is_view_active(trx->read_view));
+			ut_ad(rec_trx_id != trx->id);
 
 			if (!trx->read_view->changes_visible(
-				    row_get_rec_trx_id(
-					    rec, clust_index, offsets),
-				    old_table->name)) {
+				    rec_trx_id, old_table->name)) {
 				rec_t*	old_vers;
 
 				row_vers_build_for_consistent_read(
@@ -2168,20 +2180,33 @@ row_merge_read_clustered_index(
 					trx->read_view, &row_heap,
 					row_heap, &old_vers, NULL);
 
-				rec = old_vers;
-
-				if (!rec) {
+				if (!old_vers) {
 					continue;
 				}
+
+				/* The old version must necessarily be
+				in the "prehistory", because the
+				exclusive lock in
+				ha_innobase::prepare_inplace_alter_table()
+				forced the completion of any transactions
+				that accessed this table. */
+				ut_ad(row_get_rec_trx_id(old_vers, clust_index,
+							 offsets) < trx->id);
+
+				rec = old_vers;
+				rec_trx_id = 0;
 			}
 
 			if (rec_get_deleted_flag(
 				    rec,
 				    dict_table_is_comp(old_table))) {
 				/* In delete-marked records, DB_TRX_ID must
-				always refer to an existing undo log record. */
-				ut_ad(row_get_rec_trx_id(rec, clust_index,
-							 offsets));
+				always refer to an existing undo log record.
+				Above, we did reset rec_trx_id = 0
+				for rec = old_vers.*/
+				ut_ad(rec == page_cur_get_rec(cur)
+				      ? rec_trx_id
+				      : !rec_trx_id);
 				/* This record was deleted in the latest
 				committed version, or it was deleted and
 				then reinserted-by-update before purge
@@ -2194,19 +2219,37 @@ row_merge_read_clustered_index(
 				   rec, dict_table_is_comp(old_table))) {
 			/* In delete-marked records, DB_TRX_ID must
 			always refer to an existing undo log record. */
-			ut_ad(rec_get_trx_id(rec, clust_index));
+			ut_d(rec_trx_id = rec_get_trx_id(rec, clust_index));
+			ut_ad(rec_trx_id);
+			/* This must be a purgeable delete-marked record,
+			and the transaction that delete-marked the record
+			must have been committed before this
+			!online ALTER TABLE transaction. */
+			ut_ad(rec_trx_id < trx->id);
 			/* Skip delete-marked records.
 
 			Skipping delete-marked records will make the
 			created indexes unuseable for transactions
 			whose read views were created before the index
-			creation completed, but preserving the history
-			would make it tricky to detect duplicate
-			keys. */
+			creation completed, but an attempt to preserve
+			the history would make it tricky to detect
+			duplicate keys. */
 			continue;
 		} else {
 			offsets = rec_get_offsets(rec, clust_index, NULL,
 						  ULINT_UNDEFINED, &row_heap);
+			/* This is a locking ALTER TABLE.
+
+			If we are not rebuilding the table, the
+			DB_TRX_ID does not matter, as it is not being
+			written to any secondary indexes; see
+			if (old_table == new_table) below.
+
+			If we are rebuilding the table, the
+			DB_TRX_ID,DB_ROLL_PTR should be reset, because
+			there will be no history available. */
+			ut_ad(rec_get_trx_id(rec, clust_index) < trx->id);
+			rec_trx_id = 0;
 		}
 
 		/* When !online, we are holding a lock on old_table, preventing
@@ -2241,6 +2284,33 @@ row_merge_read_clustered_index(
 			doc_id = 0;
 		}
 
+		ut_ad(row->fields[new_trx_id_col].type.mtype == DATA_SYS);
+		ut_ad(row->fields[new_trx_id_col].type.prtype
+		      == (DATA_TRX_ID | DATA_NOT_NULL));
+		ut_ad(row->fields[new_trx_id_col].len == DATA_TRX_ID_LEN);
+		ut_ad(row->fields[new_trx_id_col + 1].type.mtype == DATA_SYS);
+		ut_ad(row->fields[new_trx_id_col + 1].type.prtype
+		      == (DATA_ROLL_PTR | DATA_NOT_NULL));
+		ut_ad(row->fields[new_trx_id_col + 1].len == DATA_ROLL_PTR_LEN);
+
+		if (old_table == new_table) {
+			/* Do not bother touching DB_TRX_ID,DB_ROLL_PTR
+			because they are not going to be written into
+			secondary indexes. */
+		} else if (rec_trx_id < trx->id) {
+			/* Reset the DB_TRX_ID,DB_ROLL_PTR of old rows
+			for which history is not going to be
+			available after the rebuild operation.
+			This essentially mimics row_purge_reset_trx_id(). */
+			byte* ptr = static_cast<byte*>(
+				row->fields[new_trx_id_col].data);
+
+			memset(ptr, 0, DATA_TRX_ID_LEN + DATA_ROLL_PTR_LEN);
+			ptr[DATA_TRX_ID_LEN] = 1U
+				<< (ROLL_PTR_INSERT_FLAG_POS - CHAR_BIT
+				    * (DATA_ROLL_PTR_LEN - 1));
+		}
+
 		if (add_autoinc != ULINT_UNDEFINED) {
 
 			ut_ad(add_autoinc
@@ -2328,6 +2398,11 @@ row_merge_read_clustered_index(
 				continue;
 			}
 
+			ut_ad(!row
+			      || !dict_index_is_clust(buf->index)
+			      || trx_id_check(row->fields[new_trx_id_col].data,
+					      trx->id));
+
 			if (UNIV_LIKELY
 			    (row && (rows_added = row_merge_buf_add(
 					buf, fts_index, old_table, new_table,
@@ -2485,7 +2560,7 @@ row_merge_read_clustered_index(
 					}
 
 					err = row_merge_insert_index_tuples(
-						trx->id, index[i], old_table,
+						index[i], old_table,
 						-1, NULL, buf, clust_btr_bulk,
 						table_total_rows,
 						curr_progress,
@@ -2597,7 +2672,7 @@ row_merge_read_clustered_index(
 					btr_bulk.init();
 
 					err = row_merge_insert_index_tuples(
-						trx->id, index[i], old_table,
+						index[i], old_table,
 						-1, NULL, buf, &btr_bulk,
 						table_total_rows,
 						curr_progress,
@@ -3444,7 +3519,6 @@ row_merge_mtuple_to_dtuple(
 }
 
 /** Insert sorted data tuples to the index.
-@param[in]	trx_id		transaction identifier
 @param[in]	index		index to be inserted
 @param[in]	old_table	old table
 @param[in]	fd		file descriptor
@@ -3459,7 +3533,6 @@ and then stage->inc() will be called for each record that is processed.
 static	MY_ATTRIBUTE((warn_unused_result))
 dberr_t
 row_merge_insert_index_tuples(
-	trx_id_t		trx_id,
 	dict_index_t*		index,
 	const dict_table_t*	old_table,
 	int			fd,
@@ -3498,7 +3571,6 @@ row_merge_insert_index_tuples(
 	ut_ad(!srv_read_only_mode);
 	ut_ad(!(index->type & DICT_FTS));
 	ut_ad(!dict_index_is_spatial(index));
-	ut_ad(trx_id);
 
 	if (stage != NULL) {
 		stage->begin_phase_insert();
@@ -3542,7 +3614,6 @@ row_merge_insert_index_tuples(
 		}
 	}
 
-
 	for (;;) {
 
 		if (stage != NULL) {
@@ -5010,7 +5081,7 @@ row_merge_build_indexes(
 				}
 
 				error = row_merge_insert_index_tuples(
-					trx->id, sort_idx, old_table,
+					sort_idx, old_table,
 					merge_files[i].fd, block, NULL,
 					&btr_bulk,
 					merge_files[i].n_rec, pct_progress, pct_cost,