In one of my latest database restore jobs, I was helping a MySQL client with issues related to mysqlbinlog and I wanted to share it here. In case you didn’t know, MySQL is a simple SQL shell with input line editing capabilities, while mysqlbinlog is a utility for processing binary logs a MySQL server. In this case, the server was MariaDB, but the utilities are the same. The database version was 10.1.38-MariaDB.

So, why use mysqlbinlog?

There are many reasons for using mysqlbinlog to process binary log files, but in this case, it was used for point-in-time recovery.

Let’s say you have an erroneous transaction that you run at 3:05 p.m. and your last full backup was run at 12 p.m. To be able to restore your database up to 3:05 p.m., you will need to restore the full backup that you took at 12 p.m. and then apply the events from your binary logs up to the time before you ran the erroneous transaction. This procedure is …

The Debian project announced their 15th release, code name Buster, on July 6th 2019. Debian 10 ships with MariaDB 10.3 and Galera. There is no separate MariaDB Connector C package, but instead MariaDB 10.3 includes MariaDB Connector C 3.0. Like most other popular Linux distributions, Debian prefers MariaDB over the Oracle owned alternative and this […]

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SQL Views Example | Views In SQL Tutorial is today’s topic. SQL views is a kind of virtual tables which have rows and columns as they are in a real database. A view can be accompanied with all the rows of a particular table or selected rows based on a certain condition. In Structured Query Language, a view is a virtual table based on the result-set of an SQL statement.

SQL VIEWS

SQL view contains rows and columns, just like the real table. The fields in the view are fields from one or more real tables in the database. You can add the SQL functions, WHERE, and JOIN statements …

Author: Robert Agar

An organization’s databases contain information that is essential for its survival. This may encompass sensitive customer data, employee records, online sales catalogs, and intellectual capital to name just a few uses of a database. The responsibility of keeping these vital resources available falls to the enterprise’s team of DBAs. Failure to properly maintain these systems can lead to serious negative consequences that can cripple a company’s ability to do business.

Almost every application of any real utility is backed by a database, which in turn is administered through a database management system (DBMS). MySQL is an extremely widely-used DBMS whose popularity is only exceeded by that of Oracle. Countless business-critical applications rely on the availability and performance of MySQL databases. A common …

SLEEP thread causing "Waiting for table metadata lock"
We might have faced some scenarios once our db connection threads are getting locked and we try to find the culprit thread id which is locking the thread, to kill and release the connections. 
Here I am going to focus on one of the scenarios when db connection threads are locked at state "waiting for table metadata lock" and when we see the processlist, we can't find any thread which is running and using the same table, i.e., all threads are in SLEEP state except the locked threads.

Such as : 
mysql [localhost:5726] {msandbox} (world) > show …

During the last conferences, I had the chance to discuss a lot with many colleagues. Some of them, like me, feel we have lost ourselves, not totally but a bit. 

I had start to think why, and this is my reasoning, not saying is right, but I think is not far from the truth.

Let us start just mentioning few events in the 2019 schedule, February Fosdem, end of May Percona live US, mid-June DataOps Barcelona, September Oracle open World, end of September-October Percona Live Europe, plus an undefined number of secondary events or MariaDB roadshows.

Where is the MySQL (and related) conference?

Do not get me wrong, we talk about MySQL a lot during each one of the above (or MariaDB, tometo/tomato). But it seems to me, that in a subtle way, the community had lost his conference.

There is nothing wrong if each company is trying to get the most out of their investment, so implicitly driving the show to get …

Two important MySQL 8.0 Shell Utilities we use regularly are the upgrade checker utility and  JSON import utility . The upgrade checker utility simplifies the pre-upgrade compatibility audit (whether MySQL server instances are ready for upgrade), We have blogged about MySQL upgrade checker utility here . The upgrade checker utility does not support checking MySQL Server instances at a version earlier than MySQL 5.7. From MySQL Shell 8.0.16, the upgrade checker utility can check the configuration file (my.cnf or my.ini) for the server instance. The utility checks for any system variables that are defined in the configuration file but have been removed in the target MySQL Server release, and also for any system variables that are …

This tutorial explains the use of MySQL aggregate functions like AVG, COUNT, SUM, MAX, MIN with the help of simple examples. Aggregate functions are a bunch of methods that operate on a set of values. They can do calculations for us and then returns one final value. For example, you may like to compute the sum of the data values in a given field. The following are aggregate functions that we are covering in this tutorial. 1. COUNT function 2. MIN function 3. MAX function 4. SUM function 5. AVG function MySQL Aggregate Functions with Examples Before we go through

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This tutorial explains MySQL OPTIMIZE TABLE statement which defrags tables and recovers unused space. We’ll describe the complete usage of this method with the help of simple examples. If your database is receiving a lot of deletes and updates calls, then it might lead to fragmentation in your MySQL data files. Therefore, a lot of unused space would go in vain, and also put a high impact on the performance. So, experts recommend that you must defrag your MySQL tables regularly. Hence, we’ll today explain how to use the MySQL OPTIMIZE TABLE to defrag tables and free up space. MySQL OPTIMIZE

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This tutorial explains MySQL CONCAT() which is a built-in String function. It takes variable no. of strings as input and concatenates them together. We’ll describe the usages of this method with the help of simple examples. MySQL string concatenation is more user-friendly than other databases such as PostgreSQL or Oracle. They provide a string concatenation operator “||” instead of a proper function. However, MS SQL server does the same job using the addition arithmetic operator (+). 1. CONCAT() Syntax 2. CONCAT() Simple Examples 4. CONCAT() with Tables Let’s now go through each of the section one by one. MySQL CONCAT()

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