Showing entries 11 to 20 of 42846
« 10 Newer Entries | 10 Older Entries »
AlmaLinux MySQL+Perl

A quick primer on Perl programs connecting to the MySQL database. It’s another set of coding examples for the AlmaLinux instance that I’m building for students. This one demonstrates basic Perl programs, connecting to MySQL, returning data sets by reference and position, dynamic queries, and input parameters to dynamic queries.

  1. Naturally, a hello.pl is a great place to start:
    #!/usr/bin/perl
    
    # Hello World program.
    print "Hello World!\n";
    

    After setting the permissions to -rwxr-xr-x. with this command:

    chmod 755 hello.pl
    

    You call it like this from the Command-Line Interface (CLI):

    ./hello.pl
    

    It prints:

    Hello World!
    
  2. Next, a connect.pl program lets us test the Perl::DBI connection to the MySQL database.
    #!/usr/bin/perl
    
    # Import libraries.
    use strict;
    use warnings;
    use v5.10;     # for …
[Read more]
The OpenLampTech Developer Newsletter is One Year Old

The OpenLampTech developer newsletter is one year old! I honestly don’t know where the past year went. Obviously, I had my nose buried in some fantastic content since OpenLampTech publishes mostly curated newsletters.

I tell you though, don’t think it isn’t a challenge adding your own thoughts and commentary to someone else’s great content because it definitely is.

I plan to continue publishing curated content in OpenLampTech but, also cover tech reporting and news-related topics that are within the MySQL, PHP, and LAMP stack ecosystems.

There seems to always be plenty to talk about in these areas so a shortage of topics won’t be the issue (I don’t think).

The Newsletter for PHP and MySQL Developers

Receive a copy of my ebook, “10 MySQL Tips For Everyone”, absolutely free when …

[Read more]
Secured MySQL InnoDB Cluster with Certificate creation using OpenSSL

This is a demo tutorial to show how we can create InnoDB Cluster with newly installed Certificate and having X509 certificate verification via MySQL Router connection.   


Recorded Video

The full process is recorded on Youtube - showing creating InnoDB Cluster with newly installed CA, Server Certificates.  The Router creation is configured with SSL Server certificate from the same CA certificate across Server nodes.   The creation of User (create user my509user identified by '....' require X509) using X509 certificate PASSTHROUGH verification via Router connection.

https://www.youtube.com/watch?v=w1xgpjw0VTw


Environment

The following environment was tested 

Oracle Linux Server release 8.6

MySQL Server 8.0.31

MySQL Shell 8.0.31 …

[Read more]
Bad Optimizer Plan on Queries Combining WHERE, ORDER BY and LIMIT

Sometimes, the MySQL Optimizer chooses a wrong plan, and a query that should execute in less than 0.1 second ends-up running for 12 minutes !  This is not a new problem: bugs about this can be traced back to 2014, and a blog post on the subject dates of 2015.  But even if this is old news, because this problem recently came to my attention, it is a problem worth writing on.

This is an improved

10 Useful mysqladmin Commands for Database Administration

In this blog post, we will show you ten useful mysqladmin commands for database administration. Mysqladmin is a client for ...

Read more

The post 10 Useful mysqladmin Commands for Database Administration appeared first on RoseHosting.

Enable innodb_print_all_deadlocks Parameter To Get All Deadlock Information in mysqld Error Log

At Percona Managed Services, sometimes clients’ applications face deadlock situations and need all historic deadlock information for application tuning.

We could get the LATEST DETECTED DEADLOCK from SHOW ENGINE INNODB STATUS\G:

….
------------------------
LATEST DETECTED DEADLOCK
------------------------
*** (1) WAITING FOR THIS LOCK TO BE GRANTED:
RECORD LOCKS space id 163 page no 3 n bits 72 index GEN_CLUST_INDEX of table `deadlock_test`.`t` trx id 78507 lock_mode X waiting
*** (2) TRANSACTION:
TRANSACTION 78508, ACTIVE 155 sec starting index read
mysql tables in use 1, locked 1
….

But how could we view all past deadlock information?

We could enable innodb_print_all_deadlocks,  and all deadlocks in InnoDB user transactions will be recorded in the MySQL error log.

Let‘s start the test.

Create the test …

[Read more]
OpenLampTech issue #52 – Substack Repost

Unbelievably, the OpenLampTech developer newsletter is one year old. Thank you so much for reading and making it possible! I appreciate each and every one of you.

The Newsletter for PHP and MySQL Developers

Receive a copy of my ebook, “10 MySQL Tips For Everyone”, absolutely free when you subscribe to the OpenLampTech newsletter.

In this week’s OpenLampTech issue #52, we have articles covering:

  • MySQL ordering with NULL
  • 7 WordPress tips for professionals
  • MySQL GUI clients for Linux
  • Working with WordPress custom tables
  • And much much more

Want to support the OpenLampTech

[Read more]
pre-FOSDEM MySQL Days 2023

pre-FOSDEM MySQL Days are back for a 5th edition !

Intersect and Except in MySQL 8.0

With the latest MySQL release (8.0.31), MySQL adds support for the SQL standard INTERSECT and EXCEPT table operators.

pre-FOSDEM MySQL Days 2023

Hello dear MySQL Community !

As you may already know FOSDEM 2023 is again going to be held in-person. FOSDEM will take place February 4th and 5th 2023.

We have also decided to put our pre-FOSDEM MySQL Day on track for a fifth edition.

As for the last edition, the event will be spread over 2 days.

These 2 extra days related to the world’s most popular open source database will take place just before FOSDEM, the 2nd and 3rd February at the usual location in Brussels.

Please don’t forget to register as soon as possible as you may already know, the seats are limited !

Register on eventbrite: https://mysqldays2023.eventbrite.com

And, please don’t forget, that if you have register for the event and you cannot make it, please free back your ticket …

[Read more]
Showing entries 11 to 20 of 42846
« 10 Newer Entries | 10 Older Entries »