2015-08-13 23:54:40 +02:00
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---
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layout: pattern
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title: Data Access Object
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folder: dao
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2015-08-15 18:03:05 +02:00
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permalink: /patterns/dao/
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2019-12-13 21:09:28 +02:00
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categories: Architectural
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2015-09-24 12:23:02 +05:30
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tags:
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- Data access
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---
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2016-01-03 21:14:30 +01:00
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## Intent
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Object provides an abstract interface to some type of database or
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other persistence mechanism.
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2019-12-07 20:01:13 +02:00
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## Class diagram
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2016-01-03 21:14:30 +01:00
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## Applicability
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Use the Data Access Object in any of the following situations
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* when you want to consolidate how the data layer is accessed
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* when you want to avoid writing multiple data retrieval/persistence layers
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2016-01-03 21:14:30 +01:00
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## Credits
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* [J2EE Design Patterns](http://www.amazon.com/J2EE-Design-Patterns-William-Crawford/dp/0596004273/ref=sr_1_2)
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