Merge from mysql-5.1 to mysql-5.5.

storage/innobase/include/row0undo.h

@@ -87,10 +87,6 @@ that index record. */
 enum undo_exec {
 	UNDO_NODE_FETCH_NEXT = 1,	/*!< we should fetch the next
 					undo log record */
-	UNDO_NODE_PREV_VERS,		/*!< the roll ptr to previous
-					version of a row is stored in
-					node, and undo should be done
-					based on it */
 	UNDO_NODE_INSERT,		/*!< undo a fresh insert of a
 					row to a table */
 	UNDO_NODE_MODIFY		/*!< undo a modify operation
@@ -108,9 +104,6 @@ struct undo_node_struct{
 	undo_no_t	undo_no;/*!< undo number of the record */
 	ulint		rec_type;/*!< undo log record type: TRX_UNDO_INSERT_REC,
 				... */
-	roll_ptr_t	new_roll_ptr;
-				/*!< roll ptr to restore to clustered index
-				record */
 	trx_id_t	new_trx_id; /*!< trx id to restore to clustered index
 				record */
 	btr_pcur_t	pcur;	/*!< persistent cursor used in searching the

storage/innobase/row/row0umod.c

@@ -68,36 +68,6 @@ check.
 If you make a change in this module make sure that no codepath is
 introduced where a call to log_free_check() is bypassed. */
 
-/***********************************************************//**
-Checks if also the previous version of the clustered index record was
-modified or inserted by the same transaction, and its undo number is such
-that it should be undone in the same rollback.
-@return	TRUE if also previous modify or insert of this row should be undone */
-static
-ibool
-row_undo_mod_undo_also_prev_vers(
-/*=============================*/
-	undo_node_t*	node,	/*!< in: row undo node */
-	undo_no_t*	undo_no)/*!< out: the undo number */
-{
-	trx_undo_rec_t*	undo_rec;
-	trx_t*		trx;
-
-	trx = node->trx;
-
-	if (node->new_trx_id != trx->id) {
-
-		*undo_no = 0;
-		return(FALSE);
-	}
-
-	undo_rec = trx_undo_get_undo_rec_low(node->new_roll_ptr, node->heap);
-
-	*undo_no = trx_undo_rec_get_undo_no(undo_rec);
-
-	return(trx->roll_limit <= *undo_no);
-}
-
 /***********************************************************//**
 Undoes a modify in a clustered index record.
 @return	DB_SUCCESS, DB_FAIL, or error code: we may run out of file space */
@@ -226,19 +196,11 @@ row_undo_mod_clust(
 	btr_pcur_t*	pcur;
 	mtr_t		mtr;
 	ulint		err;
-	ibool		success;
-	ibool		more_vers;
-	undo_no_t	new_undo_no;
 
 	ut_ad(node && thr);
 
 	log_free_check();
 
-	/* Check if also the previous version of the clustered index record
-	should be undone in this same rollback operation */
-
-	more_vers = row_undo_mod_undo_also_prev_vers(node, &new_undo_no);
-
 	pcur = &(node->pcur);
 
 	mtr_start(&mtr);
@@ -286,20 +248,6 @@ row_undo_mod_clust(
 
 	trx_undo_rec_release(node->trx, node->undo_no);
 
-	if (more_vers && err == DB_SUCCESS) {
-
-		/* Reserve the undo log record to the prior version after
-		committing &mtr: this is necessary to comply with the latching
-		order, as &mtr may contain the fsp latch which is lower in
-		the latch hierarchy than trx->undo_mutex. */
-
-		success = trx_undo_rec_reserve(node->trx, new_undo_no);
-
-		if (success) {
-			node->state = UNDO_NODE_PREV_VERS;
-		}
-	}
-
 	return(err);
 }
 
@@ -847,7 +795,6 @@ row_undo_mod_parse_undo_rec(
 	trx_undo_update_rec_get_update(ptr, clust_index, type, trx_id,
 				       roll_ptr, info_bits, trx,
 				       node->heap, &(node->update));
-	node->new_roll_ptr = roll_ptr;
 	node->new_trx_id = trx_id;
 	node->cmpl_info = cmpl_info;
 }

storage/innobase/row/row0undo.c

@@ -276,25 +276,6 @@ row_undo(
 		node->roll_ptr = roll_ptr;
 		node->undo_no = trx_undo_rec_get_undo_no(node->undo_rec);
 
-		if (trx_undo_roll_ptr_is_insert(roll_ptr)) {
-
-			node->state = UNDO_NODE_INSERT;
-		} else {
-			node->state = UNDO_NODE_MODIFY;
-		}
-
-	} else if (node->state == UNDO_NODE_PREV_VERS) {
-
-		/* Undo should be done to the same clustered index record
-		again in this same rollback, restoring the previous version */
-
-		roll_ptr = node->new_roll_ptr;
-
-		node->undo_rec = trx_undo_get_undo_rec_low(roll_ptr,
-							   node->heap);
-		node->roll_ptr = roll_ptr;
-		node->undo_no = trx_undo_rec_get_undo_no(node->undo_rec);
-
 		if (trx_undo_roll_ptr_is_insert(roll_ptr)) {
 
 			node->state = UNDO_NODE_INSERT;