js-orm

'js-orm' is the abbrevation for JavaScript-Sqlite OR-Mapping Library. After SQLite was successfully ported to javascript by 'emscripten', vast works can be done based on the Sqlite Javascript version. This library is a simple wrap up for the Sqlite. With this library, it will be able to easily do the conversion between object/array and sqlite row(s). Furthermore, a storage for SQlite database is made possible on Chrome and Firefox, which make life easier.

The main works includes:

1 Wrap a table/object level into the Class 'Table'

1.1 Manage the metadata of a object/table
constructor(name, column[]),
- Initialize the metadata from constructor.
- Normally, only table name will be provided and level column[] empty,
- since the table structure can be retrieved from following 2 functions
retrieveStructure(db),
- Reload the DB Structure from Sqlite database and stores as metadata in object
loadDDL(ddlSQL)
- load from a ddlSQL for Table definition

1.2 Simplify DDL based on the metadata definition
create(db), truncate(db), drop(db)
- Provide corresponding DDL statement to simplify the command
- e.g. db.exec('DELETE TABLE '+tablename+';');
- will be converted to tableObject.drop();

1.3 Simplify DML for upsert/delete on Array/Object Level
delete(db, where)
- Straight wrap up for the delete statement with in the Table
Arr :
- insertArray(db, []), upsertArray(db, [])
-- insert/upsert the given array to specific table
-- Note, the order that data stored in the array shall be the same as create DDL SQL
Obj :
- insertObject(db, obj), upsertObject(db, obj)
-- insert/upsert the given object to specific table
- getDefaultObject()
-- Important Feature, User do not need provide another definition of specific class for table
-- The system automatically create one using reflection
-- The conversion between 'Table Columns' and 'Class Fields' are completed by Inflection.js

1.4 Simplify Select Retrieval. It Automatically converts result to corresponding object
getObjects(db, where) - retrieve an array of objects

1.5 Create 2 more classes (Column, Sequence) for holding metadata and database operations
Column: colName, colType, colPrimaryKey
Sequence: constructor(0), currentValue(), nextValue()


2 Create a sqlUtil to store the data in Browser's LocalStorage

2.1 Load from LocalStorage
Load(filename) - files can be loaded when the page refresh/reopen
2.2 Save to LocalStorage
Save(filename) - whenever needed, the whole Sqlite database will be serialized and saved

3 Requires: SQlite.js, Inflection.js, Strings.js, HexStreamReader.js, HexStreamWriter.js


Hu, Ying-Hao(hyinghao@hotmail.com) - May, 2013
Feel free to comment and to provide advices/suggestions.