This week I noticed (yet another) customer issue related to the output produced by mysqladmin debug command (or when mysqld process gets SIGHUP signal). I mean the output generated by the mysql_print_status() function. In this issue the content of the output was misinterpreted. I've seen this in the past more than once, and requested to document the output properly, but it never happened for a reason that there is an internal feature request to put this information elsewhere, in Performance Schema or Information Schema. The bug ended up with "Won't fix" status.

Surely I complained in a comment and on Facebook, and then …

The original idea of this series was to publish one post per week, but it seems every other week I have some special topic that well deserves a dedicated post. Last week I had no time to complete my writing because of long (and, I hope, useful) Howto post on replacing corrupted partition using non-corrupted one from other server in replication setup. But I had links and notes collected in a draft that I am going to complete now.

First of all, during the previous week I had time to submit two more talks for the  …

Oracle released MySQL 5.7.15 recently, earlier than expected. The reason for this "unexpected" release is not clear to me, but it could happen because of a couple of security related internal bug reports that got fixed:

• "It was possible to write log files ending with .ini or .cnf that later could be parsed as option files. The general query log and slow query log can no longer be written to a file ending with .ini or .cnf. (Bug #24388753)
• Privilege escalation was possible by exploiting the way REPAIR TABLE used temporary files. (Bug #24388746)"

Let me concentrate on the most important fixes to bugs and problems reported by Community users. …

For some reason I do not see numerous public announcements about recent MySQL 5.7.13 release, even though it happened a couple of days ago formally. Maybe that's because we do not have any really "big" new features in this release (new ->> operator for introduced though for those who, unlike me, care about JSON). Still there are many fixes for bugs previously reported by Community (or Oracle engineers, but still in public bugs database), and I'd like to discuss some of them.

Let me start with the bug that was NOT fixed though, Bug #81093, "mysqld_multi not included in mysql-community-server package", reported by Georgi Iovchev and …

This Log Buffer Edition gathers a wide sample of blogs and then purifies the best ones from Oracle, SQL Server and MySQL.

Oracle:

• If you take a look at the “alter user” command in the old 9i documentation, you’ll see this: DEFAULT ROLE Clause.
• There’s been an interesting recent discussion on the OTN Database forum regarding “Index blank blocks after a large update that was rolled back.”
• 12c Parallel Execution New Features: 1 SLAVE distribution
• Index Tree Dumps in Oracle 12c …

The ALTER TABLE statement syntax is explained in the manual at:

http://dev.mysql.com/doc/refman/5.6/en/alter-table.html

To put it simply, there are two ways you can alter the table to use a new character set.

1. ALTER TABLE tablename DEFAULT CHARACTER SET utf8;

This will alter the table to use the new character set as the default, but as a safety mechanism, it will only change the table definition for the default character set. That is, existing character fields will have the old character set per column. For example:

mysql> create table mybig5 (id int not null auto_increment primary key,      
    -> subject varchar(100) ) engine=innodb default charset big5;
Query OK, 0 rows affected (0.81 sec)

mysql> show create table …

While most of the talk recently has mostly been around the new changes in MySQL 5.6 (and that is understandable), I have had lately some very interesting cases to deal with, with respect to the Metadata Locking related changes that were introduced in MySQL 5.5.3. It appears that the implications of Metadata Locking have not been covered well, and since there are still a large number of MySQL 5.0 and 5.1 installations that would upgrade or are in the process of upgrading to MySQL 5.5, I thought it necessary to discuss what these implications exactly are.

The post Implications of Metadata Locking Changes in MySQL 5.5 appeared first on ovais.tariq.

This is the low-level view of data dictionary language (DDL) operations in the InnoDB storage engine in MySQL 5.6. John Russell gave a more high-level view in his blog post April 2012 Labs Release – Online DDL Improvements. MySQL before the InnoDB Plugin

Traditionally, the MySQL storage engine interface has taken a minimalistic approach to data definition language. The only natively supported operations were CREATE TABLE, DROP TABLE and RENAME TABLE. Consider the following example:

CREATE TABLE t(a INT);
INSERT INTO t VALUES (1),(2),(3);
CREATE INDEX a ON t(a);
DROP TABLE t;

The CREATE INDEX statement would be executed roughly as follows:

CREATE TABLE temp(a INT, INDEX(a));
INSERT INTO temp SELECT * FROM t;
RENAME TABLE t TO temp2;
RENAME TABLE temp TO t;
DROP …

Background Knowledge

The progress of a task in TaskFreak! is shown as a percentage value and is not exactly visually appealing to quickly spot the progress. With a few minor alterations we can show the percentage completed bar that fills as the task progresses and a gradient bar indicating the progress along with the percentage value.

This solution was posted by Searcher at Re: Taskfreak Customizing Status.

Solution

1. Edit at line #268 as shown below.
   Cod Before

   268	<th width="<?php echo FRK_STATUS_LEVELS * 2; ?>%" onclick="freak_sort('statusKey')" colspan="< ?php echo FRK_STATUS_LEVELS ?>" class="sortable">< ?php echo (FRK_STATUS_LEVELS == 1)?'X':$langForm['status']; …

Background Knowledge

The Search Plugin for TaskFreak! created by DaDaemon and xdu v0.0.1 (March 26, 2007) was designed to create a simple, quick search capability of the tasks title and description. As well it only searched through he current task view (tasks visible at the time) and tasks that are not completed. For some this was not what was desired and would rather have the Search Plugin search through all tasks weather completed or not and as well search through the comments of tasks along with the title and description. I’ll show you how this is done using Searcher, bchristie and davidlmansfield instructions posted on the TaskFreak! Forums.

Solution – Add the Ability to Search All Tasks

Edit the “index.php” located in …