Changes between Version 29 and Version 30 of S3/S3Model/SuperEntities

Timestamp:

03/03/14 10:56:04 (8 years ago)

Author:

Dominic König

Comment:

--

S3/S3Model/SuperEntities

@@ -46 +46 @@
 === Defining an Instance of a Super-Entity ===
 
-To make a table an instance of a super-entity, you can use {{{s3db.configure()}}}:
+A table is declared an instance of a super-entity by configuring the {{{super_entity}}} hook (continuing the example from above):
 
-{{{
-s3db.configure(table, super_entity = db.sit_situation)
+{{{#!python
+
+        # Define the instance table
+        tablename = "my_instance_table"
+        table = self.define_table(tablename,
+                                  # Instance table must have the super ID:
+                                  self.super_link("my_super_id", "my_super_entity"),
+                                  Field("start_date", "datetime"),
+                                  Field("end_date", "datetime"),
+                                  *s3_meta_fields())
+
+        # Configure the instance table
+        self.configure("my_instance_table",
+
+                       # Configure the super entity
+                       super_entity = "my_super_entity",
+                      )
+
 }}}
 
-By default, all fields that the table and the super-entity have in common will be mirrored in the super-entity ("shared fields"). You can override this by specifying a list of fields to be mirrored by the super-entity.
+By default, all fields which have the same name in super-entity and instance table will become shared fields.
 
-{{{
-s3db.configure(table,
-               super_entity = db.sit_situation,
-               sit_situation_fields = ["datetime"])
-}}}
+If only a subset of these fields shall be shared, or the shared fields have different names in super entity and instance table, you can define a field mapping like this:
 
-In case your table uses different names for the shared fields, you can use a dict instead to specify a mapping:
+{{{#!python
 
-{{{
-s3db.configure(table,
-               super_entity = db.sit_situation,
-               sit_situation_fields = dict(datetime="timestmp", location_id="location_id"))
+        # Define the instance table
+        tablename = "my_instance_table"
+        table = self.define_table(tablename,
+                                  # Instance table must have the super ID:
+                                  self.super_link("my_super_id", "my_super_entity"),
+                                  Field("first_date", "datetime"),
+                                  Field("last_date", "datetime"),
+                                  *s3_meta_fields())
+
+        # Configure the instance table
+        self.configure("my_instance_table",
+
+                       # Configure the super entity
+                       super_entity = "my_super_entity",
+
+                       # Map the "first_date" field in my_instance_table to "start_date" in my_super_entity
+                       my_super_entity_fields = {"start_date": "first_date"},
+                  )
+
 }}}
 === Linking to a Super-Entity ===