Changes between Version 14 and Version 15 of CompositePrimaryKeyDesignNotes
- Timestamp:
- Sep 1, 2012, 11:42:16 PM (13 years ago)
Legend:
- Unmodified
- Added
- Removed
- Modified
-
CompositePrimaryKeyDesignNotes
v14 v15 5 5 == Design Questions == 6 6 7 * ''How do you define multiple primary keys?'' 7 === How do you define multiple primary keys? === 8 8 9 9 The "neatest" solution would be to allow primary_key=True on multiple fields but this may be precluded by other design considerations. 10 10 11 * ''How do you foreign key onto a table with a composite foreign key?'' 11 === How do you foreign key onto a table with a composite foreign key? === 12 12 13 13 The primary key is a set of the columns. 14 14 15 * ''What do you use for .get(pk=foo) with a composite primary key?'' 15 === What do you use for .get(pk=foo) with a composite primary key? === 16 16 17 17 The primary key is a set of the columns. 18 18 19 The likely solution is to use a set, though there is mention of the comment framework overlapping with this.19 There is mention of the comment framework overlapping with this. 20 20 21 * ''How does Admin map a url to an object?'' 21 === How does Admin map a url to an object? === 22 22 23 23 Possible solutions (for a key with the value {{{ { val_foo, val_bar, val_baz } }}}: 24 24 25 25 * {{{/appname/modulename/val_foo,val_bar,val_baz/}}} 26 26 27 27 How to deal with values containing commas? Should be able to be handled with some nice url escaping. 28 28 29 29 * {{{/appname/modulename/val_foo/val_bar/val_baz/}}} 30 30 31 * ''The columns of a key are a set, and have no implicit order. How to deal with identity between different orders of the same set?'' 31 === How to deal with identity between different orders of the same set? === 32 33 The columns of a key are a set, and have no implicit order. This means the key {{{ { val_foo, val_bar, val_baz } }}} is identical to {{{ { val_baz, val_foo, val_bar } }}} and so on for all permutations. How should URLs be parsed to reflect this identity? 32 34 33 35 == Affected Areas == … … 57 59 Expect there is a large amount of work in here making sure all the model inspection and form generation works. 58 60 59 U rlto object mapping.61 URL to object mapping. 60 62 61 63 === Serialization ===