# Aurora MySQL database engine updates: 2017-05-15 (version 1.13) (Deprecated)
**Version:** 1.13
**Note**
We enabled a new feature - SELECT INTO OUTFILE S3 - in Aurora MySQL version 1.13 after the initial release, and have updated the release notes to reflect that change.
Aurora MySQL 1.13 is generally available. All new database clusters, including those restored from snapshots, will be created in Aurora MySQL 1.13. You have the option, but are not required, to upgrade existing database clusters to Aurora MySQL 1.13. With version 1.13 of Aurora, we are using a cluster patching model where all nodes in an Aurora DB cluster are patched at the same time. We are enabling zero-downtime patching, which works on a best-effort basis to preserve client connections through the patching process. For more information, see [ Maintaining an Amazon Aurora DB cluster](https://docs.aws.amazon.com/AmazonRDS/latest/AuroraUserGuide/USER_UpgradeDBInstance.Maintenance.html) in the *Amazon Aurora User Guide*.
## Zero-downtime patching
The zero-downtime patching (ZDP) feature attempts, on a *best-effort* basis, to preserve client connections through an engine patch. For more information about ZDP, see [ Using zero-downtime patching](https://docs.aws.amazon.com/AmazonRDS/latest/AuroraUserGuide/AuroraMySQL.Updates.Patching.html#AuroraMySQL.Updates.ZDP) in the *Amazon Aurora User Guide*.
## New features:
+ **SELECT INTO OUTFILE S3** – Aurora MySQL now allows you to upload the results of a query to one or more files in an Amazon S3 bucket. For more information, see [ Saving data from an Amazon Aurora MySQL DB cluster into text files in an Amazon S3 bucket](https://docs.aws.amazon.com/AmazonRDS/latest/AuroraUserGuide/AuroraMySQL.Integrating.SaveIntoS3.html) in the *Amazon Aurora User Guide*.
## Improvements:
+ Implemented truncation of CSV format log files at engine startup to avoid long recovery time. The `general_log_backup`, `general_log`, `slow_log_backup`, and `slow_log` tables now don't survive a database restart.
+ Fixed an issue where migration of a database named **test** would fail.
+ Improved stability in the lock manager's garbage collector by reusing the correct lock segments.
+ Improved stability of the lock manager by removing invalid assertions during deadlock detection algorithm.
+ Re-enabled asynchronous replication, and fixed an associated issue which caused incorrect replica lag to be reported under no-load or read-only workload. The replication pipeline improvements that were introduced in version 1.10. These improvements were introduced in order to apply log stream updates to the buffer cache of an Aurora Replica. which helps to improve read performance and stability on Aurora Replicas.
+ Fixed an issue where autocommit=OFF leads to scheduled events being blocked and long transactions being held open until the server reboots.
+ Fixed an issue where general, audit, and slow query logs could not log queries handled by asynchronous commit.
+ Improved the performance of the logical read ahead (LRA) feature by up to 2.5 times. This was done by allowing pre-fetches to continue across intermediate pages in a B-tree.
+ Added parameter validation for audit variables to trim unnecessary spaces.
+ Fixed a regression, introduced in Aurora MySQL version 1.11, in which queries can return incorrect results when using the SQL\$1CALC\$1FOUND\$1ROWS option and invoking the FOUND\$1ROWS() function.
+ Fixed a stability issue when the Metadata Lock list was incorrectly formed.
+ Improved stability when sql\$1mode is set to PAD\$1CHAR\$1TO\$1FULL\$1LENGTH and the command `SHOW FUNCTION STATUS WHERE Db='string'` is executed.
+ Fixed a rare case when instances would not come up after Aurora version upgrade because of a false volume consistency check.
+ Fixed the performance issue, introduced in Aurora MySQL version 1.12, where the performance of the Aurora writer was reduced when users have a large number of tables.
+ Improved stability issue when the Aurora writer is configured as a binlog worker and the number of connections approaches 16,000.
+ Fixed a rare issue where an Aurora Replica could restart when a connection gets blocked waiting for Metadata Lock when running DDL on the Aurora master.
## Integration of MySQL bug fixes
+ With an empty InnoDB table, it's not possible to decrease the auto\$1increment value using an ALTER TABLE statement, even when the table is empty. (Bug \$169882)
+ MATCH() ... AGAINST queries that use a long string as an argument for AGAINST() could result in an error when run on an InnoDB table with a full-text search index. (Bug \$117640261)
+ Handling of SQL\$1CALC\$1FOUND\$1ROWS in combination with ORDER BY and LIMIT could lead to incorrect results for FOUND\$1ROWS(). (Bug \$168458, Bug \$1 16383173)
+ ALTER TABLE does not allow to change nullability of the column if foreign key exists. (Bug \$177591)