Title: GemStone/S Indexed Collection Primer
Speaker: Dale Henrichs
Thu, August 21, 12:00pm – 12:30pm


Abstract: GemStone/S indexes provide a way to locate specific objects in a collection by value. Indexing a Collection creates internal structures such as balanced trees (Btrees). Only a few message sends are needed to lookup a value or range of values in the indexing structures. When collections are indexed, they can return results without having to iterate the collection or send messages to each object.

Queries may be formulated using a Selection Block:

collection select: {:each | each.age >= 18 }

or programmatically using instances of GsQuery (new in GemStone/S 3.2):

(GsQuery fromString: 'each.age >= 18' on: collection) queryResult.

The new query syntax provides more flexibility in forming queries using the new '|' and 'not' messages:

(each.age <= 40) | (each.job = 'librarian') not

In this talk Dale will provide a detailed overview of the capabilities of GemStone/S indexes.

Bio: Dale Henrichs has been working in Smalltalk since 1985 when he developed an internal application on the Tektronix 4404. The internal application was used at Tektronix for at least 25 years and may still be in use today! Since 1985 he has been lucky enough to work in Smalltalk nearly full-time, spending the last 15 years at GemStone give or take a couple of years.

Slides
	http://www.slideshare.net/esug/gem-stoneindexing-esug2014
	
Video Part1: https://www.youtube.com/watch?v=XvLFwJfn-uQ
Video Part2: https://www.youtube.com/watch?v=wd_b0k3732I