Changes between Version 1 and Version 2 of TracDev/ScratchPad/DataModels

Timestamp:

Jul 30, 2015, 2:21:42 AM (9 years ago)

Author:

Ryan J Ollos

Comment:

Document comments from #11701.

TracDev/ScratchPad/DataModels

@@ -12 +12 @@
 
 We should standardize on `NULL` again. When retrieving `NULL` values from the database, we get `None` in Python. If needed, we can carry on this distinct meaning yet manipulate it as a string by converting `None` to the special value [apidoc:api/trac_util_text#trac.util.text.empty empty]. See e.g. what we do for  [source:trunk/trac/ticket/model.py@11111:127,137#L110 ticket fields].
+
+=== Class methods
+
+Class methods, one example being `select`, are used for table-wide queries.
+
+The signature of the `select` method is not consistent across all classes.
+The `Milestone` class has an [browser:/trunk/trac/ticket/model.py?rev=13060&marks=1129#L1121 include_completed] parameter in the `select` method.
+We could reconcile the inconsistency by having `where`, `limit` and `order_by` parameters on each method, with the parameters directly mapping to phrases in the SQL query.
+This would make the methods more generally useful to plugin developers.
+
+Not only is the interface inconsistent, but also the return value. In most cases a generator is returned by `select`, however some `select` methods return a list:
+* [browser:trunk/trac/ticket/model.py@13060:1137#L1128​]
+* [browser:trunk/trac/ticket/model.py@13060:1234#L1222​]