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Displaying posts with tag: Scripting (reset)
Scripting continued

Since I have been discussing scripting lately I thought I would continue with another topic I touched on briefly - backups.

I have written and modified the following script over the last few years. I have used it (and continue to use it) with multiple clients. It uses Percona's Xtrabackup to take the backup (although it can be easily modified to use mysqldump instead).

First the script


day_of_week=`date +%a`
password=`cat /root/.ssh/.backup_password`

# run backup
echo ' ' > $report
echo 'The backup is now beginning:' >> $report
echo ' ' …

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Interviewing tip..

I've been involved in a number of interviews over the last few weeks as a client has been loking for a MySQL DBA. When you are looking for position as a DBA in a large scale environement there are some very important things you have to know.

You absolutely must know a scripting language. In a smaller environment this often isn't necessary. You will live and die by this in a large environment. I asked every applicant one specific question..if you had to change a mysql server variable on a pool of 100 mysql servers how would you do this? It's easy when it's one,two or even a dozen servers. just log in, change the my.cnf and change it "on the fly" if you can. Restart mysql if you can't.

You going to do that to 100 servers? It will take all day and be prone to failures. Scripting is the key here. Even just bash shell scripting can be very powerful. In another post I will cover a simple bash script to loop through a …

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How To Sort Columns of MySQL Data on a Web Page With Perl

A friend of mine was building a web site so his customers could view his current inventory of transportation containers, and he asked me for help on how to sort the rows of information that appeared on his site. So, in this post, I will give you a quick example on how to sort columns on a web page.

First, let’s start with an inventory database that we will build in MySQL:

CREATE TABLE `inventory` (
`item_name` varchar(30) NOT NULL,
`item_SKU` varchar(20) NOT NULL,
`item_cost` decimal(4,2) NOT NULL,

Next, here are some SQL statements to populate the MySQL database with some sample data.

use …
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Automatically Download MySQL Enterprise Monitor Graphs as PNG Files Using Perl

I was giving a presentation of the MySQL’s Enterprise Monitor* application to a client recently. I was demonstrating the “graphs” section of MEM, where you can monitor MySQL sessions, connections, replication latency and more with 60+ graphs. Usually, you view the graphs from within the MEM Enterprise Dashboard (via a web browser). But the client asked if there was a way to automatically download graphs. I wasn’t sure why he wanted to download the graphs (I didn’t ask), but I knew it wasn’t possible by using MEM alone. However, in the past I have written Perl scripts to automatically download files from web sites, so I thought I would see if it was possible with MEM.

*The MySQL Enterprise Monitor (MEM) continuously monitors your MySQL servers and alerts you to potential …
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Using MySQL and Perl to Create, Edit and Delete Information Via a Web Page

A friend of mine was asking me for my recommendation of a good desktop database program to use to keep track of his inventory of cargo containers. I suggested to him that he should use MySQL and write a web page interface to do everything that he needed. He then reminded me that he is a lawyer by trade, and that he doesn’t have any computer programming experience. Then I remembered that he has almost zero computer skills. And his Texas Hold-Em skills are even worse, but I don’t mind taking his money. In his case, he should just use a notepad and a pencil. (As for the question – what is a lawyer doing with cargo containers? – that is a different story.)

If he did decide to broaden his horizons a bit, he could easily write his own software web application for creating and storing almost any kind of data. In this post, I will show you how to create a MySQL database and then the web pages needed to create new addresses, edit the same …

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Checking on the Progress of Large DML Commands in MySQL Using Perl – Part Two

Part Two of Two: Checking on database activity when running a large DML (Data Manipulation Language) statement – such as INSERT, DELETE, UPDATE or SELECT.

Part Two: Monitoring the activity via Perl and SHOW ENGINE INNODB STATUS. (part of the InnoDB Monitors)

In part one, I showed you how to use a Perl script to insert a million rows of dummy data into a table. I needed a large database in order to test a Perl script that I would use to monitor the activity when running a large DML statement.

The original reason for creating both of these scripts was to find a quick way to see if a large DML statement was actually being executed. A customer was performing some modifications on …

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Checking on the Progress of Large DML Commands in MySQL Using Perl – Part One

Part One of Two: Checking on database activity when running a large DML (Data Manipulation Language) statement – such as INSERT, DELETE, UPDATE or SELECT.

Part One: Inserting a million rows into a database.

A friend of mine had asked a question – “Is there any way you can track how far you have advanced in a slow-moving ALTER or OPTIMIZE statement?”. A customer was performing some modifications on a database with tens of millions of rows, and they wanted to be able to see if the command was making any progress.

Since the customer was using the InnoDB storage engine, I thought of a way that you could check on the progress – but only given the fact that nothing else (major) was happening in the database (more on this reason later).

With InnoDB, you can …

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Using MySQL, Perl and jQuery to Auto-Populate a Form Field on a Web Page

If you have ever built a form on a web page, you might have used a drop-down menu to display the choices available for a particular field. With a drop-down menu, you restrict the choices a user may select so that the user doesn’t enter invalid data (among other reasons). If a user misspells an entry, then a subsequent search for that value would not produce a found result.

A friend of mine who runs an online forum sent me an email about a problem he was having. He was trying to modify an existing registration web page using jQuery to auto-populate the state names, and then pass the state abbreviation back to his MySQL database. Believe it or not, he was actually having problems with people knowing their own state abbreviation. He had searched and found an example of what he wanted to do, but he couldn’t get it to work. So, I took the …

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Steve Jobs, you will be missed. Greatly.

I remember my first computer. It was a TI-99/4A. I bought it back in 1982 (I think), and it cost around $300. The entire computer fit inside what looked like a really thick keyboard. It had a slot on the right for cartridges, and I had a cassette tape drive that I used for backing up the BASIC computer programs that I wrote. I thought that it was a great computer at the time, but I really didn’t have anything to compare it to. The games were the best part of the computer (really the only fun part – my BASIC skills were lacking). And even though the games were fairly lame by even 1982 standards, but they were still plenty of fun to play.

I also remember when I saw a Macintosh for the first time. I had followed Apple for some time, but I had never had the opportunity to actually see a Macintosh. I think it was in 1987 or 1988, when I was a student at the University of Georgia. I believe it was a Mac SE, and it had one megabyte of RAM and a …

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Using MySQL to Import and Retrieve Blobs and Display as Image Files in HTML

I received a phone call from a friend of mine who had some questions about storing image files as blobs in MySQL. He wanted to design a web site that would allow someone to upload an image, and then that image would be stored in the MySQL database for viewing later. He stated that he was going to be storing thousands of images. I mentioned that it might be better to store the images on the file system, and then to just store the location of the image in the database. But, he still wanted to know how to do it and would decide which solution he would incorporate later.

I already had a Perl script that allowed me to upload files to a web site, as I would give out this URL to people that wanted to send me large files. And, I know that you can store images (and other files) in MySQL as a blob, but I wasn’t sure how to display the blob as an image in HTML (once I had retrieved it from the MySQL database). A search on Google provide bits and …

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