Tombstoning on top of Windows Azure Table Store
Thursday December 31st 2009, 4:32 pm
Filed under:
SOA/Web/Etc.
After command journaling probably the next most effective protection
against application logic errors is tombstoning (keeping a copy of the last
version of a deleted row). In this article I propose a design for adding
tombstoning to Windows Azure Table Store using two tables, a main table
and a tombstone table.
This article is part of a series. Click here to see summary and complete list of articles in the series.
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Thoughts on implementing a command journal
Wednesday December 30th 2009, 2:39 pm
Filed under:
SOA/Web/Etc.
I had previously concluded that command journaling (creating a
journal of all the external user commands and internal maintenance
commands I issue) is really useful for recovering from self inflicted data
corruption. In this article I look into the various techniques I can use
to implement a command journal so as to trade off between system
performance and the journal’s utility in recovery.
This article is part of a series. Click here to see summary and complete list of articles in the series.
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Techniques to Ease Recovering from Self Inflicted Data Corruption
Monday December 28th 2009, 12:02 pm
Filed under:
SOA/Web/Etc.
In a previous article I argued that even with the protections Windows
Azure Table Store provides for my data I can still screw things up myself
and so need to put in place protections against my own mistakes. Below
I walk through the three scenarios I previously listed and explain how
command journaling, tombstoning and versioning could make recovering
from my errors much easier.
This article is part of a series. Click here to see summary and complete list of articles in the series.
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The Limits of Command Journals
Wednesday December 23rd 2009, 6:32 pm
Filed under:
SOA/Web/Etc.
In a previous article I argued that I needed some kind of
journaling/backup for my Windows Azure Tables in order to make it
easier for me to recover from my own screw ups. One type of journaling
I suggested was command journaling. In this article I look at the
practical limitations of command journals and conclude that while they
are (somewhat) useful for notifying users who might have been affected
by data corruption they aren’t likely in the general case to be re-playable
so their real value is probably less than it might appear.
This article is part of a series. Click here to see summary and complete list of articles in the series.
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Do I need to backup/journal my Windows Azure Table Store?
Tuesday December 22nd 2009, 5:25 pm
Filed under:
SOA/Web/Etc.
Windows Azure provides a highly scalable, reliable, fault resistent table
store. So in theory my service can dump data into the table store and
walk away secure in the knowledge that I’ll get back what I put in and
that the data will be there when I need it. So is there any reason I should
care about backing up or journaling my Windows Azure Tables? As I
argue below the answer is - yes. But the reason isn’t to protect me against
Azure’s mistakes, it’s to protect me from myself.
This article is part of a series. Click here to see summary and complete list of articles in the series.
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Chef’s Choice SmartKettle Model 688
Monday December 21st 2009, 8:38 pm
Filed under:
reviews
I love green tea and its variants such as jasmine and genmaicha. But these teas only taste good to me when made with hot water around 160′s. Anything hotter just turns them into an acid brew. But seriously, sticking a thermometer into a cup to measure the heat just wasn’t working out. I bemoaned the lack of a kettle with a thermostat to save me. Thankfully Wired clued me in to a great solution – the Chef’s Choice SmartKettle Model 688. My wife was nice enough to buy me one, it works great and my green tea tastes outstanding!