diff options
Diffstat (limited to 'sql/ha_innodb.cc')
| -rw-r--r-- | sql/ha_innodb.cc | 10 |
1 files changed, 10 insertions, 0 deletions
diff --git a/sql/ha_innodb.cc b/sql/ha_innodb.cc index 0af1fb7b50a..ea8eaf6653e 100644 --- a/sql/ha_innodb.cc +++ b/sql/ha_innodb.cc @@ -3486,6 +3486,16 @@ ha_innobase::records_in_range( prebuilt->trx->op_info = (char*)""; + /* The MySQL optimizer seems to believe an estimate of 0 rows is + always accurate and may return the result 'Empty set' based on that. + The accuracy is not guaranteed, and even if it were, for a locking + read we should anyway perform the search to set the next-key lock. + Add 1 to the value to make sure MySQL does not make the assumption! */ + + if (n_rows == 0) { + n_rows = 1; + } + DBUG_RETURN((ha_rows) n_rows); } |