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Object Reference Mapping (1:1 relation)

Naming conventions

All the tables and columns in the database are all lowercase. (Which is quite handy with an Mysql database because the names are case-sensitive if the underlying file system is also case-sensitive. So Mysql Names are case sensitive on Linux but not on Windows.)

Tablenames are plural.

Prototype names start with upper case and are camel case. Prototype names are singular.

Property- Object- and Collection-Mapping start with lower case and are also camel case.

Foreign keys are prefixed with the name of the table they are referring to.


DB schema


Mapping

Lets map the image_data to our image!

Image/type.properties
   imageData          = Object(ImageData)
   imageData.local    = image_id
   imageData.foreign  = images_image_id

This code is in the type.properties file of our Image prototype. We specify which prototype should be mapped with the Object() instruction. You have to specify the name of the prototype here. To the properties.local and .foreign you must assign the names of database columns.