MySQL “No space left on device from storage engine”

We have planned for archiving the data to improve the DB performance and to reclaim the space. We were evaluating Compression in InnoDB and TokuDB. To find out the best compression method. We started benchmarking the compression ratio between InnoDB and TokuDB. Everything goes well for some time, but after a few hours got an … Continue reading MySQL “No space left on device from storage engine”

Handling case sensitive column in pt-archiver

To copy the data of the particular column of the table to another table/server, We have an option to export the data as CSV and import the data back to a different table. But when the table size is large and we need to copy the data only for the required data to the target … Continue reading Handling case sensitive column in pt-archiver

Faster Load data outfile in MySQL

While exporting the table with MySQL native utility, we don't have any control on the process, and also there will be no progress update as well on the process completion. So when exporting the larger table will consume high resource utilization and also the disk space usage will also be high. MySQL shell utility will … Continue reading Faster Load data outfile in MySQL

Troubleshooting an unique key addition during pt-online-schema-change

We all tried various alternative methods for modifying the table structure, but pt-online-schema-change (pt-osc) is the most convenient and preferred method for performing the alter online. It has more granular control too. But it may lead to data loss if proper precautionary steps are not taken care of. In this blog, we are going to … Continue reading Troubleshooting an unique key addition during pt-online-schema-change

Maintenance of MySQL Binary logs

In this blog, we are going to discuss the Maintenance of binary logs. Before going into our topic, let’s recall the basics of binary logs. Binary logs           Binary logs contain all the changes and records that take place in any database. It will log the statements like CREATE, ALTER, DELETE, INSERT and UPDATE. It will … Continue reading Maintenance of MySQL Binary logs

Replication Filters in MySQL an Overview

What are Replication Filters in MySQL? A replication filter is used to filter out the necessary databases and tables that will be replicated in the replica. The replication filter can be set either in my. cnf or the command line. The change made in those databases will be logged in binary log files. The filter … Continue reading Replication Filters in MySQL an Overview

Introduction to MySQL Parallel query in AWS Aurora

Aurora has a salient feature "Parallel query", Which will be more beneficial for analytical workload environments. Before going to deep dive on this particular feature, let us understand the basis of Aurora. Aurora Archiecture Key feature The key feature of Aurora is simple data synchronisation among the nodes. The sync latency will be too low … Continue reading Introduction to MySQL Parallel query in AWS Aurora

Major SST methods In XtraDB / MariaDB Cluster and its supporting files.

Galera replicates the data across the cluster in a virtually synchronous fashion. Based on the availability of cluster nodes the type of data transfer can vary. The important factor which decides the type of data transfer required here is the existing write set in gcache. Galera Cluster stores write-sets in a special cache called the … Continue reading Major SST methods In XtraDB / MariaDB Cluster and its supporting files.

MariaDB/XtraDB Cluster Default Disk Files and its Significance

Galera is the core tech behind the Percona XtraDB Cluster and MariaDB Cluster. When using the Galera cluster we might have come across multiple files in the data directory beyond the Native MySQL or InnoDB Files. It is always good to understand these files to know what is happening internally. Each file present in the … Continue reading MariaDB/XtraDB Cluster Default Disk Files and its Significance

MySQL ERROR Log Table Explained

Over the decades we have been reading the MySQL error log from the server system file, if there are any issues in MySQL or any unknown restart happened , generally we look at the mysql error log. By default MySQL error log can be found in the default path /var/log/mysqld.log , or it can be … Continue reading MySQL ERROR Log Table Explained