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10 Newer Entries Showing entries 31 to 40 of 96 10 Older Entries

Displaying posts with tag: myisam (reset)

On Hot Backups and Restore using XtraBackup
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Backups are an integral and very important part of any system. Backups allow you to recover your data and be up and running again, in the advent of problems such as system crashes, hardware failures or users deleting data by mistake. I had been evaluating backup solution for a while but to be honest I really wasn't satisfied with the solutions available until I came across XtraBackup and I am loving it since. In this post I intend on showing how to do backups and restores using XtraBackup.

Limiting table disk quota in MySQL
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Question asked by a student: is there a way to limit a table’s quote on disk? Say, limit a table to 2GB, after which it will refuse to grow? Note that the requirement is that rows are never DELETEd. The table must simply refuse to be updated once it reaches a certain size.

There is no built-in way to limit a table’s quota on disk. First thing to observe is that MySQL has nothing to do with this. It is entirely up to the storage engine to provide with such functionality. The storage engine is the one to handle data storage: how table and keys are stored on disk. Just consider the difference between MyISAM’s .MYD & …

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What is this MySQL file used for?
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MySQL keeps many different files, some contain real data, some contain meta data. Witch ones are important? Witch can your throw away?

This is my attempt to create a quick reference of all the files used by MySQL, whats in them, what can you do if they are missing, what can you do with them.

When I was working for Dell doing Linux support my first words to a customer where “DO YOU HAVE COMPLETE AND VERIFIED BACKUP?” Make one now before you think about doing anything I suggest here.

You should always try to manage your data through a MySQL client.  If things have gone very bad this may not be possible. MySQL may not start. If …

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Comparing InnoDB to MyISAM Performance
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The MySQL performance team in Oracle has recently completed a series of benchmarks comparing Read / Write and Read-Only performance of MySQL 5.5 with the InnoDB and MyISAM storage engines.

Compared to MyISAM, InnoDB delivered 35x higher throughput on the Read / Write test and 5x higher throughput on the Read-Only test, with 90% scalability across 36 CPU cores.

A full analysis of results and MySQL configuration parameters are documented in a new whitepaper


In addition to the benchmark, the …






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Comparing InnoDB to MyISAM Performance
Employee_Team +0 Vote Up -0Vote Down

The MySQL performance team in Oracle has recently completed a series of benchmarks comparing Read / Write and Read-Only performance of MySQL 5.5 with the InnoDB and MyISAM storage engines.

Compared to MyISAM, InnoDB delivered 35x higher throughput on the Read / Write test and 5x higher throughput on the Read-Only test, with 90% scalability across 36 CPU cores.

A full analysis of results and MySQL configuration parameters are documented in a new whitepaper


In addition to the benchmark, the new …






  [Read more...]
Moving from MyISAM to Innodb or XtraDB. Basics
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I do not know if it is because we're hosting a free webinar on migrating MyISAM to Innodb or some other reason but recently I see a lot of questions about migration from MyISAM to Innodb.

Webinar will cover the process in a lot more details though I would like to go over basics in advance. You can also check my old post on this topic about Moving MyISAM to Innodb as well as …

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Why mysqldump is converting my tables from InnoDB to MyISAM?
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First of all: mysqldump is not converting tables. It is something else. Here is the story:

One of my clients had a case when they were migrating to a new mysql server: they used mysqldump to export data from the old server (all InnoDB) and imported it to the new server. When finished, all the tables became MyISAM on the new server. So they asked me this question:
“Why mysqldump is converting my tables from InnoDB to MyISAM?”

First of all we made sure that the tables are InnoDB on the old server. It was true.
Second we run “show engines” on the new server:





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Common MySQL Scalability Mistakes
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This week I was one of the presenters at the first Surge Scalability Conference in Baltimore. An event that focused not just on one technology but on what essential tools, technologies and practices system architects need to know about for successfully scaling web applications.

While MySQL is an important product in many environments, it is only one component for a successful technology stack and for many organizations is one of several products that manage your data.

My presentation was on the common MySQL …

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Converting myisam tables to innodb
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Why should you convert myisam tables to innodb ?

For the perfectly simple reason that innodb tables do not get locked by concurrent selects & inserts. So if you find that your myisam table is suffering for too many locks - due to concurrent selects and inserts, it is time for you to covert the table to innodb.

The simple query which does the trick is

Alter table myisam_table_name engine =

mysql hack - altering huge tables
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You have a huge mysql table - maybe 100 GB. And you need to run alter on it - to either add an index, drop an index, add a column or drop a column. If you run the simple mysql "alter table" command, you will end up spending ages to bring the table back into production.

Here is a simple hack to get the thing done. The benefit of the hack is that the alter runs quite fast. But since this is a hack

10 Newer Entries Showing entries 31 to 40 of 96 10 Older Entries

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