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Wiki source code of WebObjects and Squeryl

Version 93.1 by Ravi Mendis on 2010/11/10 04:58
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1 = Squeryl ~= //SQL-like// DSL for Scala =
2
3 Advantages of Squeryl over EOF:
4
5 * Concurrent
6 ** Spawns multiple database connections
7 ** Issues database transactions concurrently
8 * Scala Actor compatible
9 ** Immutable object model/graph
10 * Strongly-typed
11 ** Better suited for database/business "logic".
12 E.g: Exploits the compiler and IDE to catch exceptions at compile time rather than at run-time.
13 * Uses Scala (functional) collection classes
14
15 = Migrating EOF -> Squeryl =
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17 In contrast to EOF Squeryl maintains its ORM information programmatically - in the classes itself and collectively in a ##schema##. And in keeping with the strongly-typed philosophy of Scala, it has no dynamic component like EOF (i.e an EO model file).
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19 EOF has the ability to generate classes in Java (and in Objective-C prior to WebObjects 4.5) as enforcing type has become customary in enterprise environments. We may exploit this feature of EOF to generate a Squeryl schema.
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21 === Preparing your EO model ===
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23 * Make sure **all** EO entities have a class name (including abstract many-To-many "join" tables). There's no support for entities marked as ##EOGenericRecord##.
24 * Mark the abstract many-To-Many join entities as ##Abstract##.
25 * (Temporary) Ensure all the model entities are in the same package. i.e ##model## <-> ##package## corresponds 1-to-1.
26
27 === Generating the Squeryl Schema ===
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29 1. Create a .eogen file for your EO model as normal. Only set the ##File Names## extension to "scala".
30 1. Use the Squeryl EO Templates:
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32 *
33 ** Entity.eotemplate [[template>>WOL:Squeryl _Entity.eotemplate]]
34 ** Entity.eotemplate [[template>>WOL:Squeryl Entity.eotemplate]]
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36 {{note title="Note"}}
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38 Any custom business "logic" will have to be manually re-written in Scala
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40 {{/note}}