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Displaying posts with tag: binary log (reset)
More Metadata Is Written Into Binary Log

In row based replication, the row data generated by DML is logged into binary log with some metadata. For example column type, type length etc. In the new release MySQL-8.0.1, more table metadata are written into binary log. All metadata together brings users and us below benefits:

  • Allows us to build robuster replication and convert row data between types smoothly.

MySQL Bug 72804 Workaround: “BINLOG statement can no longer be used to apply query events”

In this blog post, we’ll look at a workaround for MySQL bug 72804.

Recently I worked on a ticket where a customer performed a point-in-time recovery PITR using a large set of binary logs. Normally we handle this by applying the last backup, then re-applying all binary logs created since the last backup. In the middle of the procedure, their new server crashed. We identified the binary log position and tried to restart the PITR from there. However, using the option

--start-position

, the restore failed with the error “The BINLOG statement of type Table_map was not preceded by a format description BINLOG statement.” This is a known bug and is reported as MySQL …

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Configuring and testing MySQL binary log

The binary log contains “events” that describe database changes. On a basic installation with default options, it's not turned on. This log is essential for accommodating the possible following requirements:

Replication: the binary log on a master replication server provides a record of the data changes to be sent to slave servers. Point in Time recovery: allow to recover a database from a full

Changed defaults between MySQL 5.6 and 5.7

MySQL 5.7 comes with many changes. Some of them are better explained than others.

I wanted to see how many changes I could get by comparing SHOW VARIABLES in MySQL 5.6 and 5.7.
The most notable ones are:

  • binlog_format: the default is now ROW. This variable affects the format of the binary log, whether you use it as a backup complement or for replication, the change means bigger binary logs and possibly side effects.
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Purging and Rotating Logs Made Easy with MySQL Utilities

The MySQL Utilities team is happy to introduce a new MySQL utility named  ‘mysqlbinlogpurge‘, which allows users to easily and safely purge binary logs on a master by determining the binary logs that are obsolete. This utility is included in MySQL Utilities
release-1.6.1 Alpha release along with ‘mysqlslavetrx‘ and ‘mysqlbinlogrotate‘. This utility enables you to purge binary logs by ensuring that any files which are in use or required by any of the slaves in a replication topology are not deleted. This is achieved by
checking which binary logs have been read on each slave. This determines the minimal set of binary log files that …

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Restore / Recover dropped MySQL database from binary logs

In this post I will share a recovery scenario of a MySQL database restore from the binary logs. Recently someone accidentally dropped an important MySQL database and the backup was not present! As we know the the binary log contains DMLs to table data and that’s where our hope lies. Luckily the binary log retention […]

New MySQL Utility to Relocate Binary Logs

We are very happy to introduce a new MySQL utility named 'mysqlbinlogmove', which is used to relocate binary log files. This utility is one of two new utilities included in MySQL Utilities release-1.6.0 Alpha. The other utility is 'mysqlgrants', which is used to display the privileges (grants) of database objects.

Note: I use "binary log" to refer to both "kinds" of binary log files (binlog and relay log files) in general, and use "binlog" to refer specifically to those that are not "relay log" files.

The mysqlbinlogmove utility allows you to move binary log files to a new location taking care of correctly updating the respective index file for you. This utility can be very useful if you want to change the location to store the binlog file and you want to move all of the binary log files. It is also handy to archive older binary log files to a new location thereby saving disk space in the server's partition.

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New MySQL Utility to Relocate Binary Logs

We are very happy to introduce a new MySQL utility named “mysqlbinlogmove“, which is used to relocate binary log files. This utility is one of two new utilities included in MySQL Utilities release-1.6.0 Alpha. The other utility is “mysqlgrants“, which is used to display the privileges (grants) of database objects.

Note: I use “binary log” to refer to both “kinds” of binary log files (binlog and relay log files) in general, and use “binlog” to refer specifically to those that are not “relay log” files.

The mysqlbinlogmove utility allows you to move binary log files to a new location taking care of correctly updating the respective index file for you. This utility can be very useful if you want to change the location to store the binlog file and you want to move all of the binary log files. It is also handy to archive older binary log files to a new location thereby saving disk …

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Multi-master data conflicts - Part 2: dealing with conflicts

In the first part of this article we examined the types of conflicts and their causes. In this part, we will analyse some of the methods available to deal with conflicts.

Pessimistic locking (or: conflicts won't happen)

Applicability: synchronous clusters with 2pc

We've covered this topic in the previous article, but it's worth repeating. If you use a synchronous cluster, you don't have conflicts. For example, MySQL Cluster ensures consistent data with updates coming from different nodes. However, MySQL Cluster is not a replacement for a MySQL server, and it has severe limitations.


Optimistic locking

Applicability: synchronous clusters without 2pc (Galera)

Conflicting transactions proceed on different nodes with local locking. The last one then …

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Binary Log Group Commit in MySQL 5.6

With the release of MySQL 5.6 binary log group commit is included, which is a feature focused on improving performance of a server when the binary log is enabled. In short, binary log group commit improve performance by grouping several writes to the binary log instead of writing them one by one, but let me digress a little on how transactions are logged to the binary log before going into the details. Before going into details about the problem and the implementation, let look at what you do to turn it on.

Nothing.

Well... we actually have a few options to tweak it, but nothing required to turn it on. It even works for existing engines since we did not have to extend the handlerton interface to implement the binary log group commit. However, InnoDB has some optimizations to take advantage of the binary log group commit implementation.

binlog_order_commits={0|1}
This is a …
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