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Search Results for: auto_increment primary key

Illustrating Primary Key models in InnoDB and their impact on disk usage

On a recent engagement I worked with a customer who makes extensive use of UUID() values for their Primary Key and stores it as char(36), and their row count on this example table has grown to …

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Multi-Valued INSERTs, AUTO_INCREMENT & Percona XtraDB Cluster

A common migration path from standalone MySQL/Percona Server to a Percona XtraDB Cluster (PXC) environment involves some measure of time where one node in the new cluster has been configured as a slave of the …

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InnoDB scalability issues due to tables without primary keys

Each day there is probably work done to improve performance of the InnoDB storage engine and remove bottlenecks and scalability issues. Hence there was another one I wanted to highlight: Scalability issues due to tables …

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STOP: DELETE IGNORE on Tables with Foreign Keys Can Break Replication

DELETE IGNORE suppresses errors and downgrades them as warnings, if you are not aware how IGNORE behaves on tables with FOREIGN KEYs, you could be in for a surprise. Let’s take a table with data as example, …

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Conflict Avoidance with auto_increment_increment and auto_increment_offset

A lot of people are running MySQL Master-Master replication pairs in Active-Passive mode for purpose of high availabilities using MMM or other solutions. Such solutions generally have one major problem – you have to be …

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Sharing an auto_increment value across multiple MySQL tables

The title is SEO bait – you can’t do it. We’ve seen a few recurring patterns trying to achieve similar – and I thought I would share with you my favorite two: Option #1: Use …

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Instrumentation and the cost of Foreign Keys

I occasionally get in to light arguments healthy discussions with students about whether or not to use Foreign Key constraints on InnoDB tables.  My standard response has always been: “it depends on how much of …

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Better Primary Keys, a Benefit to TokuDB’s Auto Increment Semantics

In our last post, Bradley described how auto increment works in TokuDB. In this post, I explain one of our implementation’s big benefits, the ability to combine better primary keys with clustered primary keys. In …

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AUTO_INCREMENT and MERGE TABLES

How would you expect AUTO_INCREMENT to work with MERGE tables ? Assuming INSERT_METHOD=LAST is used I would expect it to work same as in case insertion happens to the last table… which does not seems …

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Long PRIMARY KEY for Innodb tables

I’ve written and spoke a lot about using short PRIMARY KEYs with Innodb tables due to the fact all other key will refer to the rows by primary key. I also recommended to use sequential …

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