MySQL Cluster

Table maintenance operations are useful for identifying and correcting database problems such as the following: – Tables that become damaged as a result of a server crash. – Slow query processing on tables. Many tools are available for performing table maintenance: MySQL Workbench MySQL Enterprise Monitor SQL (DML) maintenance statements Utilities: mysqlcheck and myisamchk Server auto-recovery SQL for Table Maintenance Operations There are multiple SQL statements for performing … [Read more...] about Beginners Guide to Implementing Table Maintenance in MySQL

Question: How to list tables inside tablespaces in a MuSQL cluster? The following query meets the aim of the question, lists the database, table name and the corresponding tablespace: SELECT DISTINCT t.table_schema, t.table_name, p.tablespace_name FROM partitions p JOIN TABLES t ON (t.table_schema=p.table_schema and t.table_name = p.table_name) WHERE t.engine='ndbcluster' and tablespace_name IS NOT NULL … [Read more...] about How to List Tables Per Tablespace In MySQL Cluster

Note: In MySQL Server 8.0.X you must use the exact same patch release of MEB as the Server, eg MySQL Server 8.0.13 requires the use of MEB 8.0.13. The Basics For *nix OSes, the document uses a shell expansion for simple naming of folders with "todays" date+time, eg shell:~ # d="$(date '+%d%b_%H%M')" shell:~ # echo $d 13Nov_1338 It is, of course, possible to adjust this as any existing naming conventions dictate. Simple high level backup / restore commands: creates an image backup ( … [Read more...] about Backup and Restore Of Group Replication Node ( MySQL 8.0 )

The Problem A replication slave cannot continue replicating from its Master. One such example is that after being stopped for a long ( or longer than anticipated ) timeframe, the BINARY LOGS required on the Master have been purged. [ERROR] [MY-013114] [Repl] Slave I/O for channel 'group_replication_recovery': Got fatal error 1236 from master when reading data from binary log: 'Cannot replicate because the master purged required binary logs. Replicate the missing transactions from elsewhere, or … [Read more...] about MySQL Server 8.0 – How to create a REPLICATION SLAVE using MEB

Each online MySQL Cluster backup receives a unique identification number. This is to ensure that there is a history of activities in the backup directory. However, this can causes problems. For example, if a system restarts, this ID counter is reset and starts again at number 1, causing problems if you didn't move earlier backups. This post will discuss how to generate unique backup ids. The best method is after each online backup operation to move the created backup directory to another … [Read more...] about How to Generate Unique IDs For MysQL Cluster Backups

A rolling restart is required when you need to restart all of the nodes in a cluster for some change to take effect. Rather than bringing down the entire cluster, you can restart each single node one by one, in order to allow the cluster to continue serving requests during the changes. Most operations can be done using this technique, such as changing config.ini settings (ie. DataMemory, MaxNoOfConcurrentTransactions, etc.). However, there is a main instance when you can not use this process … [Read more...] about How to Perform a Rolling Restart of MySQL NDB Cluster

There are three types of nodes that you might want to add to an existing MySQL Cluster: mysqld (API) nodes, management server nodes, and data nodes. Adding a new mysqld (API) node In order to add a new mysqld node, you simply need to add the new [mysqld] section to the config.ini and then perform a rolling upgrade. After you have done this, then you can start up the new mysqld node and it will have all of the cluster data available. To do this, following you would follow these steps: Edit … [Read more...] about How to Add New Nodes To an Existing MySQL Cluster Setup

The ability to add MySQL Cluster data nodes while the cluster is still up and running is known as performing an "online" addition of nodes. This became available in MySQL Cluster starting with the 6.4.0 release version. Performing an online addition to the cluster allows for increased availability since there is no downtime and also allows a more flexible management of the cluster resources. Certain changes of the Cluster configuration will require a complete restart of the Cluster and even a … [Read more...] about How to Add Data Nodes to MySQL Cluster without Restarting the Cluster (version 6.4 and later)

It is possible but not advisable. One of the main reasons to run a cluster is to provide redundancy: in order to enjoy the full benefits of this redundancy, each node should reside on a separate machine. If you place multiple nodes on a single machine and that machine fails, you lose all of those nodes. Given that MySQL Cluster can be run on commodity hardware loaded with a low-cost (or even no-cost) operating system, it is well worth the expense of an extra machine or two in order to … [Read more...] about Can MySQL Cluster Run Multiple Nodes On a Single Server