Changes in MySQL 5.7.20:
Audit Log Notes
Event-matching filter rules for the audit_log plugin now support an abort element, which can be used to prevent qualifying events from executing. For more information, see Audit Log Filtering. This capability can be used, for example, to augment the capabilities of MySQL Enterprise Firewall, which blocks SQL statements on a per-user basis, by writing audit filtering rules that match statements and block them based on characteristics of the statements themselves.
Deprecation and Removal Notes
Previously, the --transaction-isolation and --transaction-read-only server startup options corresponded to the tx_isolation and tx_read_only system variables. For better name correspondence between startup option and system variable names, transaction_isolation and transaction_read_only have been created as aliases for tx_isolation and tx_read_only. The tx_isolation and tx_read_only variables are now deprecated and will be removed in MySQL 8.0. Applications should be adjusted to use transaction_isolation and transaction_read_only instead.
The query cache is now deprecated and is removed in MySQL 8.0. Deprecation includes these items:
* The FLUSH QUERY CACHE and RESET QUERY CACHE statements.
* The SQL_CACHE and SQL_NO_CACHE SELECT modifiers.
* These system variables: have_query_cache, ndb_cache_check_time, query_cache_limit, query_cache_min_res_unit, query_cache_size, query_cache_type, query_cache_wlock_invalidate.
* These status variables: Qcache_free_blocks, Qcache_free_memory, Qcache_hits, Qcache_inserts, Qcache_lowmem_prunes, Qcache_not_cached, Qcache_queries_in_cache, Qcache_total_blocks.
The mysql client by default strips comments in statements sent to the server, and this behavior is controlled using --skip-comments (strip comments), and --comments (preserve comments).
Comment stripping is now deprecated. This feature and the options to control it will be removed in a future MySQL release.
These syntax constructs for table and column references are now deprecated and will be removed in a future version of MySQL. Instances of these constructs should be changed to remove the leading period.
* .col_name
* .tbl_name
* .tbl_name.col_name
Security Notes
Certificates automatically generated by mysqld and mysql_ssl_rsa_setup now use X509 v3 rather than v1.
The keyring_okv plugin now supports password-protecting the key file used for secure connections. See Using the keyring_okv KMIP Plugin.
Bugs Fixed
c0bf9d5314