Re: [Maria-developers] Feature Request - Working auto_inc rement on BlackHole Engine

On 05/15/2013 11:27 PM, Jocelyn Fournier wrote:

Hi Gordan,

Le 15/05/13 22:18, Gordan Bobic a écrit :

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On 05/15/2013 09:06 PM, Michael Widenius wrote:

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Hi!

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>> "Gordan" == Gordan Bobic writes:

Gordan> How difficult would be be to implement working Gordan> auto-increment functionality on the BlackHole engine?

Gordan> This would be really useful for what I'm trying to do at Gordan> the moment. Since it is not available and there are no Gordan> sequences in MariaDB and MySQL, I have to resort to a Gordan> hack such as a single-int-field table doing the Gordan> auto-increment, and an insert trigger on the blackhole Gordan> table to insert a null into the auto-increment Gordan> tracking table, get LAST_INSERT_ID() to set the Gordan> value in the auto-increment table, and then delete Gordan> the record.

What problem is that you wanted to solve? Normally blackhole is used just for creating a slave of a slave that doesn't have to hold any data (only the logs).

The problem is a huge volume logging application that needs to have uniquely enumerated records for auditing purposes.

Have you tried TokuDB engine ?

It isn't suitable for what I am doing in this case - note that the blackhole engine in this case suits all of my requirements except for the working auto_increment functionality. I don't need to store the data on these nodes, merely binlog it up for further processing downstream. Gordan