Safety of statements with a LIMIT clause¶

Performance improvement on relay log position update¶

Performance improvement on source and connection status updates¶

Writing FLUSH Commands to the Binary Log¶

FLUSH commands, such as FLUSH SLOW LOGS, are not written to the binary log if the system variable binlog_skip_flush_commands is set to ON.

In addition, the following changes were implemented in the behavior of read_only and super_read_only modes:

• When read_only is set to ON, any FLUSH ... command executed by a normal user (without the SUPER privilege) are not written to the binary log regardless of the value of the binlog_skip_flush_command variable.
• When super_read_only is set to ON, any FLUSH ... command executed by any user (even by those with the SUPER privilege) are not written to the binary log regardless of the value of the binlog_skip_flush_command variable.

An attempt to run a FLUSH command without either SUPER or RELOAD privileges results in the ER_SPECIFIC_ACCESS_DENIED_ERROR exception regardless of the value of the binlog_skip_flush_command variable.

variable binlog_skip_flush_commands¶

Version Info:	8.0.15-5 – Introduced
Command Line:	Yes
Config File:	Yes
Scope:	Global
Dynamic:	Yes
Default Value:	OFF

When binlog_skip_flush_command is set to ON, FLUSH ... commands are not written to the binary log. See Writing FLUSH Commands to the Binary Log for more information about what else affects the writing of FLUSH commands to the binary log.

Binary Log User Defined Functions¶

To implement Point in Time recovery, we have added the binlog_utils_udf. The following user-defined functions are included:

The basic syntax for get_binlog_by_gtid() is the following:

• get_binlog_by_gtid(string) [AS] alias

  Usage: SELECT get_binlog_by_gtid(string) [AS] alias

  Example:

  CREATE FUNCTION get_binlog_by_gtid RETURNS STRING SONAME 'binlog_utils_udf.so';
  SELECT get_binlog_by_gtid("F6F54186-8495-47B3-8D9F-011DDB1B65B3:1") AS result;
  +--------------+
  | result       |
  +==============+
  | binlog.00001 |
  +--------------+
  
  DROP FUNCTION get_binlog_by_gtid;
  

The basic syntax for get_last_gtid_from_binlog() is the following:

• get_last_gtid_from_binlog(string) [AS] alias

  Usage: SELECT get_last_gtid_from_binlog(string) [AS] alias

  Example:

  CREATE FUNCTION get_last_gtid_from_binlog RETURNS STRING SONAME 'binlog_utils_udf.so';
  SELECT get_last_gtid_from_binlog("binlog.00001") AS result;
  +-----------------------------------------+
  | result                                  |
  +=========================================+
  | F6F54186-8495-47B3-8D9F-011DDB1B65B3:10 |
  +-----------------------------------------+
  
  DROP FUNCTION get_last_gtid_from_binlog;
  

The basic syntax for get_gtid_set_by_binlog() is the following:

• get_gtid_set_by_binlog(string) [AS] alias

  Usage: SELECT get_gtid_set_by_binlog(string) [AS] alias

  Example:

  CREATE FUNCTION get_gtid_set_by_binlog RETURNS STRING SONAME 'binlog_utils_udf.so';
  SELECT get_gtid_set_by_binlog("binlog.00001") AS result;
  +-------------------------+
  | result                  |
  +=========================+
  | 11ea-b9a7:7,11ea-b9a7:8 |
  +-------------------------+
  
  DROP FUNCTION get_gtid_set_by_binlog;
  

The basic syntax for get_binlog_by_gtid_set() is the following:

• get_binlog_by_gtid_set(string) [AS] alias

  Usage: SELECT get_binlog_by_gtid_set(string) [AS] alias

  Example:

  CREATE FUNCTION get_binlog_by_gtid_set RETURNS STRING SONAME 'binlog_utils_udf.so';
  SELECT get_binlog_by_gtid_set("11ea-b9a7:7,11ea-b9a7:8") AS result;
  +---------------------------------------------------------------+
  | result                                                        |
  +===============================================================+
  | bin.000003                                                    |
  +---------------------------------------------------------------+
  
  DROP FUNCTION get_binlog_by_gtid_set;
  

The basic syntax for get_first_record_timestamp_by_binlog() is the following:

• get_first_record_timestamp_by_binlog(TIMESTAMP) [AS] alias

  Usage: SELECT get_first_record_timestamp_by_binlog(TIMESTAMP) [AS] alias

  Example:

  CREATE FUNCTION get_first_record_timestamp_by_binlog RETURNS STRING SONAME 'binlog_utils_udf.so';
  SELECT FROM_UNIXTIME(get_first_record_timestamp_by_binlog("bin.00003") DIV 1000000) AS result;
  +---------------------+
  | result              |
  +=====================+
  | 2020-12-03 09:10:40 |
  +---------------------+
  
  DROP FUNCTION get_first_record_timestamp_by_binlog;
  

The basic syntax for get_last_record_timestamp_by_binlog() is the following:

• get_last_record_timestamp_by_binlog(TIMESTAMP) [AS] alias

  Usage: SELECT get_last_record_timestamp_by_binlog(TIMESTAMP) [AS] alias

  Example:

  CREATE FUNCTION get_last_record_timestamp_by_binlog RETURNS STRING SONAME 'binlog_utils_udf.so';
  SELECT FROM_UNIXTIME(get_last_record_timestamp_by_binlog("bin.00003") DIV 1000000) AS result;
  +---------------------+
  | result              |
  +=====================+
  | 2020-12-04 04:18:56 |
  +---------------------+
  
  DROP FUNCTION get_last_record_timestamp_by_binlog;