diff options
| -rw-r--r-- | mysys/hash.c | 19 |
1 files changed, 19 insertions, 0 deletions
diff --git a/mysys/hash.c b/mysys/hash.c index 75135a470c9..1ba80dc6fd3 100644 --- a/mysys/hash.c +++ b/mysys/hash.c @@ -572,6 +572,25 @@ my_bool hash_update(HASH *hash,byte *record,byte *old_key,uint old_key_length) previous->next=pos->next; /* unlink pos */ /* Move data to correct position */ + if (new_index == empty) + { + /* + At this point record is unlinked from the old chain, thus it holds + random position. By the chance this position is equal to position + for the first element in the new chain. That means updated record + is the only record in the new chain. + */ + if (empty != idx) + { + /* + Record was moved while unlinking it from the old chain. + Copy data to a new position. + */ + data[empty]= org_link; + } + data[empty].next= NO_RECORD; + DBUG_RETURN(0); + } pos=data+new_index; new_pos_index=hash_rec_mask(hash,pos,blength,records); if (new_index != new_pos_index) |