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Search Results for: multiple connection

What happens when your application cannot open yet another connection to MySQL

Have you ever experienced a situation where one moment you can connect to the MySQL database and the next moment  you cannot, only to be able to connect again a second later? As you may …

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Percona Toolkit for MySQL with MySQL-SSL Connections

I recently had a client ask me how to use Percona Toolkit tools with an SSL connection to MySQL (MySQL-SSL). SSL connections aren’t widely used in MySQL due to most installations being within an internal …

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mysqld_multi: How to run multiple instances of MySQL

The need to have multiple instances of MySQL (the well-known mysqld process) running in the same server concurrently in a transparent way, instead of having them executed in separate containers/virtual machines, is not very common. Yet …

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Prevent MySQL downtime: Set max_user_connections

One of the common causes of downtime with MySQL is running out of connections. Have you ever seen this error? “ERROR 1040 (00000): Too many connections.” If you’re working with MySQL long enough you surely …

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Multiple purge threads in Percona Server 5.1.56 and MySQL 5.6.2

Part of the InnoDB duties, being an MVCC-implementing storage engine, is to get rid of–purge–the old versions of the records as they become obsolete.  In MySQL 5.1 this is done by the master InnoDB thread.  …

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MySQL Connection Timeouts

Sometimes on very busy MySQL server you will see sporadic connection timeouts, such as Can’t connect to MySQL server on ‘mydb’ (110). If you have connects timed in your application you will see some successful …

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MySQL Limitations Part 4: One thread per connection

This is the third in a series on what’s seriously limiting MySQL in core use cases (links: part 1, 2, 3). This post is about the way MySQL handles connections, allocating one thread per connection …

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Sharing an auto_increment value across multiple MySQL tables

The title is SEO bait – you can’t do it. We’ve seen a few recurring patterns trying to achieve similar – and I thought I would share with you my favorite two: Option #1: Use …

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What would make MySQL Multiple Queries Usable ?

MySQL Has API to run Multiple Queries at once. This feature was designed mainly with saving network round trip in mind and got a little traction due to associated security risks and not significant gains …

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Are PHP persistent connections evil ?

As you probably know PHP “mysql” extension supported persistent connections but they were disabled in new “mysqli” extension, which is probably one of the reasons some people delay migration to this extension. The reason behind …

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