The Chandler Project Blog » chandlerdb

Receiving notifications about changes to items

Andi Vajda — Wed, 08 Mar 2006 23:09:57 +0000

To support the requirements of Chandler, the repository had to implement a richer set of notifications than what was originally offered with attribute monitors.

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Collection items

Andi Vajda — Wed, 08 Mar 2006 19:42:21 +0000

A collection item is an item that wraps an abstract set of items or bi-directional item references.

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Using collection indexes to find items

Andi Vajda — Tue, 24 Jan 2006 23:03:22 +0000

During last week’s sprints I was asked to see how easy it was to import mail into Chandler from a local mailbox. Thanks to Python’s mailbox and email packages, the mailbox parsing was trivial. Similarly, Chandler’s domain model can represent email items and has a number of APIs that make creating such items from a raw email string very easy.

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New posts on the chandlerdb blog

Andi Vajda — Mon, 23 Jan 2006 23:45:35 +0000

It’s been a while since I posted anything on the chandlerdb blog. That is now corrected with a few new posts about repository backup, recent performance improvements and version purging.

Reclaiming repository disk space

Andi Vajda — Mon, 23 Jan 2006 23:18:07 +0000

Chandler’s repository is versioned. Like a subversion source code repository, changes to items are saved into the repository as coherent versions. This enables to later merge together changes that occurred in different threads or processes instead of serializing changes by locking resources.

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Performance improvements

Andi Vajda — Mon, 23 Jan 2006 22:43:35 +0000

In the run up to the Chandler 0.6 release, a lot of performance improvements were made to the repository codebase. Many areas of Chandler were also reworked somewhat to make better use of performance critical repository features.

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Backing up and restoring a repository

Andi Vajda — Mon, 23 Jan 2006 22:05:01 +0000

Chandler’s repository is intended to store a lot of data that one cannot afford to lose. It should come as no surprise that doing regular backups is strongly recommended. There are a few repository APIs, currently accessible from Chandler’s “Test” menu or from Chandler’s --restore command line option, that make it possible to backup and later restore a repository’s files.

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Abstract sets of items

Andi Vajda — Fri, 22 Jul 2005 17:00:54 +0000

A new type of value was added to the data model that combines sets of items using set arithmetic. Abstract sets of items do not store any item references but evaluate their operator against the sets or collections they wrap to implement appartenance tests and iteration. In addition, abstract sets notify their owner item whenever an item is added or removed from a backing collection.

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Sets of literal values

Andi Vajda — Mon, 11 Jul 2005 15:59:34 +0000

Python 2.4 introduced a set type. The repository data model was enhanced to support attributes of cardinality ’set’ or values of type ‘//Schema/Core/Set’.

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Improved date and time support

Andi Vajda — Sun, 10 Jul 2005 17:23:30 +0000

Until recently, date and time value support was implemented in the data model with the help of Egenix’ mx extensions library. With the Python 2.3 release, new types for date and time values were introduced. The repository now makes use of them.

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