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Search Results for: large tables

How FLUSH TABLES WITH READ LOCK works with Innodb Tables

Many backup tools including Percona Xtrabackup, MyLVMBackup and others use FLUSH TABLES WITH READ LOCK to temporary make MySQL read only. In many cases the period for which server has to be made read only …

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How to recover deleted rows from an InnoDB Tablespace

In my previous post I explained how it could be possible to recover, on some specific cases, a single table from a full backup in order to save time and make the recovery process more …

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Optimizing InnoDB for creating 30,000 tables (and nothing else)

Once upon a time, it would have been considered madness to even attempt to create 30,000 tables in InnoDB. That time is now a memory. We have customers with a lot more tables than a …

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Dynamic row format for MEMORY tables

The latest Percona Server release has one new feature: now MEMORY tables can have BLOB and TEXT columns, and VARCHAR columns will not waste space due to implicit extension to CHAR.

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Sharing an auto_increment value across multiple MySQL tables (revisited)

A couple of weeks ago I blogged about Sharing an auto_increment value across multiple MySQL tables. In the comments, a few people wrote in to suggest alternative ways of implementing this.  I just got around …

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Loading Tables with TokuDB 4.0

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Often, the first step in evaluating and deploying a database is to load an existing dataset into the database. In the latest version, TokuDB makes use of multi-core parallelism to speed up loading (and new …

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Reasons for run-away main Innodb Tablespace

So you’re running MySQL With innodb_file_per_table option but your ibdata1 file which holds main (or system) tablespace have grown dramatically from its starting 10MB size. What could be the reason of this growth and what …

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TokuDB Indexes are NOT in-memory (and not hash tables either)

Another plug for Bradley’s talk Thursday morning at the MySQL User’s conference. Spending the day talking to DBA’s and other potential users of TokuDB, I (Zardosht) noticed the same question/theme come up numerous times in …

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Innodb performance gotcha w Larger queries.

Couple of days ago I was looking for a way to improve update performance for the application and I was replacing single value UPDATE with multiple value REPLACE (though I also saw the same problem …

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Finding what Created_tmp_disk_tables with log_slow_filter

Whilst working with a client recently I noticed a large number of temporary tables being created on disk.

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