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Version 27 by zumbrunn on 06. October 2009, 15:21

30  var book books = Book.query().equals("title", req.params.title).select();

Version 26 by zumbrunn on 06. October 2009, 15:18

13The current Git snapshot implements preliminary query functionality for the googlestore, berkeleystore, filestore, memstore backends. Note that while googlestore and berkeleystore use indxing and query functionality provided by the underlying libraries and APIs, filestore and memstore use unindexed, brute force query implementations that require a full read of the queried objects. Berkeleystore
28
29Query example:
30  var book = Book.query().equals("title", req.params.title).select();

Version 25 by hannes on 04. September 2009, 17:47

76* save(props, entitiy, tx) entitiy) - save object to db
77* remove(key, tx) remove(key) - remove object from db

Version 24 by hannes on 01. September 2009, 18:05

47
48=== Store interface
49
50A persistent class is created by calling the Storable.defineClass() method with a store implementation and a class name.
51
52  // define Storable base class
53  defineClass(org.helma.wrappers.Storable);
54  // create a new store
55  var store = new MyStore('/db');
56  // create a persistent Book object
57  var Book = Storable.defineClass(store, "Book");
58  
59  // Book objects can now be accessed via the
60  // Storable data access methods and scripted
61  // via Book.prototype
62  Book.prototype.toString = function() this.title;
63  
64  var b = new Book({title: 'JS for dummies'});
65  b.save();
66
67A store implementation can be any JavaScript object that implements the folloing functions:
68
69* all(type) - get all objects of one type
70* get(type, id) - get a single object for its id
71* query() - get a query object
72* getEntity(key|properties) - get an entity object
73* getKey(entity) - get the key object
74* getProps(entitiy) - get the properties object
75* equalKeys(key1, key2) - check if keys are equal
76* save(props, entitiy, tx) - save object to db
77* remove(key, tx) - remove object from db
78* getId(key) - get the object id
79

Version 23 by hannes on 08. August 2009, 12:59

13The current Git snapshot implements preliminary query functionality for the googlestore, berkeleystore, filestore, memstore backends. Note that while googlestore uses the indexes and berkeleystore use indxing and query functionality provided by Google's datastore APIthe underlying libraries and APIs, filestore and memstore use unindexed, brute force query implementations that require a full read of the queried objects. Berkeleystore

Version 22 by hannes on 30. July 2009, 18:34

21* <b>query.less('propertyName', propertyValue)</b> Returns a subquery with the added less-than filter.
22
26* <b>query.greaterEquals('propertyName', propertyValue)</b> Returns a subquery with the added greater-than greater-than-or-equals filter.

Version 21 by hannes on 30. July 2009, 18:10

15* <b>Type.query()</b>query()</b> Returns a query object for the Storable type represented by the given constructor.
16 Returns a query object for the Storable type represented by the given constructor.
17* <b>query.equals('propertyName', propertyValue)</b>propertyValue)</b> Returns a subquery with the added equality filter.
18 Returns a subquery with the added equality filter.
19* <b>query.less('propertyName', propertyValue)</b>propertyValue)</b> Returns a subquery with the added less-than filter.
20 Returns a subquery with the added less-than filter.
21* <b>query.less('propertyName', propertyValue)</b>propertyValue)</b> Returns a subquery with the added less-than filter.
22 Returns a subquery with the added less-than filter.
23* <b>query.lessEquals('propertyName', propertyValue)</b>propertyValue)</b> Returns a subquery with the added less-than-or-equals filter.
24 Returns a subquery with the added less-than-or-equals filter.
25* <b>query.greater('propertyName', propertyValue)</b>propertyValue)</b> Returns a subquery with the added greater-than filter.
26 Returns a subquery with the added greater-than filter.
27* <b>query.greaterEquals('propertyName', propertyValue)</b>propertyValue)</b> Returns a subquery with the added greater-than filter.
28 Returns a subquery with the added greater-than filter.
29* <b>query.select('propertyName')</b>)</b> Returns an array containing the result of the query. If propertyName argument is defined, the result array only contains the given property of the selected objects. Otherwise, it contains the whole objects.
30 Returns an array containing the result of the query. If propertyName argument is defined, the result array only contains the given property of the selected objects. Otherwise, it contains the whole objects.

Version 20 by hannes on 30. July 2009, 18:09

10Collecting links of prior art and to collect more ideas on this.
11==== Preliminary Design
12
13The current Git snapshot implements preliminary query functionality for the googlestore, filestore, memstore backends. Note that while googlestore uses the indexes provided by Google's datastore API, filestore and memstore use unindexed, brute force query implementations that require a full read of the queried objects.
14
15* <b>Type.query()</b>
16 Returns a query object for the Storable type represented by the given constructor.
17
18* <b>query.equals('propertyName', propertyValue)</b>
19 Returns a subquery with the added equality filter.
20
21* <b>query.less('propertyName', propertyValue)</b>
22 Returns a subquery with the added less-than filter.
23
24* <b>query.less('propertyName', propertyValue)</b>
25 Returns a subquery with the added less-than filter.
26
27* <b>query.lessEquals('propertyName', propertyValue)</b>
28 Returns a subquery with the added less-than-or-equals filter.
29
30* <b>query.greater('propertyName', propertyValue)</b>
31 Returns a subquery with the added greater-than filter.
32
33* <b>query.greaterEquals('propertyName', propertyValue)</b>
34 Returns a subquery with the added greater-than filter.
35
36* <b>query.select('propertyName')</b>
37 Returns an array containing the result of the query. If propertyName argument is defined, the result array only contains the given property of the selected objects. Otherwise, it contains the whole objects.
38
12
13Collecting links of prior art and to collect more ideas on this.
14

Version 19 by simono on 29. July 2009, 16:49

2* *Berkeley storable|http://github.com/hns/berkeleystore/tree/master* backend for the Helma NG Storable interface based on the Berkeley DB

Version 18 by robi42 on 19. July 2009, 02:40

23* *LINQ |http://msdn.microsoft.com/de-at/library/bb308959(en-us).aspx* ("language-integrated query" developed by MS for .NET), JS impl. available:

Version 17 by robi42 on 19. July 2009, 02:15

23* *LINQ |http://msdn.microsoft.com/de-at/library/bb308959(en-us).aspx*aspx* ("language-integrated query" developed by MS for .NET)

Version 16 by robi42 on 19. July 2009, 02:08

23* *LINQ |http://msdn.microsoft.com/de-at/library/bb308959(en-us).aspx*
24** *jLinq |http://www.hugoware.net*
25** *JSLINQ |http://www.codeplex.com/JSLINQ*

Version 15 by simono on 06. July 2009, 15:27

20* Django's query interface http://docs.djangoproject.com/en/dev/topics/db/queries/#retrieving-specific-objects-with-filters (replaced named parameters with a JS object)
21** only django's ORM part could be packaged as jar (jython2.5)
22** enhanced googlestore query interface nearly identical to djangos

Version 14 by sleepnova on 25. June 2009, 19:20

Version 13 by sleepnova on 25. June 2009, 19:19

9=== Query API design* (planning)design
11==== ReferencesPrior Art
15* App Engine DatastoreDatastore *Low-level API - Query |http://code.google.com/intl/en/appengine/docs/java/javadoc/com/google/appengine/api/datastore/Query.html*
16** *Low-level API - Query |http://code.google.com/intl/en/appengine/docs/java/javadoc/com/google/appengine/api/datastore/Query.html*
18* Mozilla ServerJS *Relational Database Interface |https://wiki.mozilla.org/ServerJS/RDBMS*
19* Persevere *JSONQuery |http://docs.persvr.org/documentation/jsonquery*
20

Version 12 by liamstask on 19. June 2009, 22:46

18** Provides Ruby-based ORM that provides nice modules that a variety of backends (rdbms and others) can mix in to provide common features like validation, lazy/eager loading, in addition to a nice query api

Version 11 by zumbrunn on 18. June 2009, 21:03

13** *A Developer's Tour - Advanced Queries | http://www|http://www.mongodb.org/display/DOCS/Advanced+Queries*
14** *Developers' Guide - Searching and Retrieving | http://www|http://www.mongodb.org/display/DOCS/Searching+and+Retrieving*
15** *Low-level API - Query | http://code|http://code.google.com/intl/en/appengine/docs/java/javadoc/com/google/appengine/api/datastore/Query.html*

Version 10 by liamstask on 18. June 2009, 18:08

17* DataMapper - http://datamapper.org/doku.php?id=docs
18** Provides nice modules that a variety of backends (rdbms and others) can mix in to provide common features like validation, lazy/eager loading, in addition to a nice query api

Version 9 by sleepnova on 18. June 2009, 17:41

12* MongoDB APIMongoDB
13** *A Developer's Tour - Advanced Queries | http://www.mongodb.org/display/DOCS/Advanced+Queriesorg/display/DOCS/Advanced+Queries*
14** *Developers' Guide - Searching and Retrieving | http://www.mongodb.org/display/DOCS/Searching+and+Retrievingorg/display/DOCS/Searching+and+Retrieving*
15* App Engine Datastore APIDatastore
16** *Low-level API - Query | http://code.google.com/intl/en/appengine/docs/java/javadoc/com/google/appengine/api/datastore/package-summarycom/intl/en/appengine/docs/java/javadoc/com/google/appengine/api/datastore/Query.htmlhtml*

Version 8 by sleepnova on 18. June 2009, 17:36

8
9=== Query API design* (planning)
10Collecting links of prior art and to collect more ideas on this.
11==== References
12* MongoDB API
13** http://www.mongodb.org/display/DOCS/Advanced+Queries
14** http://www.mongodb.org/display/DOCS/Searching+and+Retrieving
15* App Engine Datastore API
16** http://code.google.com/intl/en/appengine/docs/java/javadoc/com/google/appengine/api/datastore/package-summary.html

Version 7 by hannes on 17. April 2009, 13:36

7* Liam Staskawicz is working on a *Helma NG module|http://bitbucket.org/liamstask/mongolovehelma/* for *MongoDB|http://www.mongodb.org/*.

Version 6 by hannes on 13. April 2009, 00:11

5* Google App Engine *datastore module|http://github.com/hns/helma-ng/blob/e102a1982e25069489c5efcd14fb829fb66fa0c9/modules/helma/googlestore.js* and *demo app|http://github.com/hns/helma-ng/tree/e102a1982e25069489c5efcd14fb829fb66fa0c9/apps/googlestore* com/hns/helma-ng/tree/35d42b5ca2f008fc00e2529d7fedea286acb1323/apps/googlestore* (*running on App Engine|http://helma-storage.appspot.com/*)

Version 5 by hannes on 12. April 2009, 23:35

5* Google App Engine *googlestore *datastore module|http://github.com/hns/helma-ng/blob/e102a1982e25069489c5efcd14fb829fb66fa0c9/modules/helma/googlestore.js* and *demo app|http://github.com/hns/helma-ng/tree/e102a1982e25069489c5efcd14fb829fb66fa0c9/apps/googlestore* (*running on App Engine|http://helma-storage.appspot.com/*)
6* *padded-ng|http://github.com/leobm/padded-ng/tree/master* is a CouchDB client by Jan-Felix Wittmann.

Version 4 by hannes on 12. April 2009, 22:40

5* Google App Engine *googlestore module|http://github.com/hns/helma-ng/blob/e102a1982e25069489c5efcd14fb829fb66fa0c9/modules/helma/googlestore.js* and *demo app|http://github.com/hns/helma-ng/tree/e102a1982e25069489c5efcd14fb829fb66fa0c9/apps/googlestore* (*running on App Engine|http://helma-storage.appspot.com/*)

Version 3 by hannes on 20. February 2009, 22:59

4* Helma NG *filestore module|http://githubmodule|helma.com/hns/helma-ng/blob/89a30cf8b6f83e8f180a6d87d45d30f57fdeefde/modules/helma/filestore.js* filestore* and *demo app|http://github.com/hns/helma-ng/tree/2ee6966a4ca6f27437c197cf769bf926a528eafc/apps/storage*

Version 2 by hannes on 20. February 2009, 20:19

1=== Current efforts
2

Version 1 by hannes on 20. February 2009, 20:17

1* *Hibernate wrapper for Helma NG|http://github.com/robi42/dbstore/tree/master* and *demo app|http://github.com/robi42/blog-ng/tree/master* by Robert Thurnher
2* Helma NG *filestore module|http://github.com/hns/helma-ng/blob/89a30cf8b6f83e8f180a6d87d45d30f57fdeefde/modules/helma/filestore.js* and *demo app|http://github.com/hns/helma-ng/tree/2ee6966a4ca6f27437c197cf769bf926a528eafc/apps/storage*
Page created by hannes on Fri Feb 20 2009 20:17:32 GMT+0100 (CET).
Page last modified by zumbrunn on Tue Oct 06 2009 15:21:55 GMT+0200 (CEST).
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