Changes between Version 5 and Version 6 of Backtracking
- Timestamp:
- Oct 16, 2009, 3:13:56 PM (15 years ago)
Legend:
- Unmodified
- Added
- Removed
- Modified
-
Backtracking
v5 v6 25 25 The attribute systemStatus is not useful to build the a version of an entity, because every entity's versions will have the same value. The attribute unique for each version is the modifier, therefore the query will look like this: 26 26 27 ''select * from entity, attribute, entity_attribute where entity.id = X && attribute.id= Y && entity_attribute.entityId = X && entity_attribute.attributeId= Y && entity. modifier = Z && attribute. modifier = Z'', where X and Y are numbers and Z is a time stamp. 27 28 {{{ 29 select * from entity, attribute, entity_attribute where entity.id = X && attribute.id= Y && entity_attribute.entityId = X && entity_attribute.attributeId= Y && entity. modifier = Z && attribute. modifier = Z 30 }}} 31 , where X and Y are numbers and Z is a time stamp. 28 32 29 33 '''Analysis of Behavior''' … … 34 38 Attribute[id:2, systemStatus:original, modifier:x] 35 39 36 * Modification of an Entity 40 * '''Modification of an Entity''' 41 37 42 A modification on an Entity will create a copy of the edited entity and its corresponding attributes (and relations). The new copy will have the value “original” in systemStatus and the current time in modifier. In the old version will be change only the attribute systemStatus from “original to copy”. 38 43 … … 45 50 Both the table entity_attribute and the table_relation should not be changed. 46 51 47 * Elimination of an Attribute 52 * '''Elimination of an Attribute''' 53 48 54 An elimination of an attribute will mean the following changes: 49 55 … … 55 61 For this case both the table entity_attribute and the table_relation should not be changed, because the reference between the attribute and the entity is used by the previous versions. 56 62 57 * Insertion of an Attribute 63 * '''Insertion of an Attribute''' 64 58 65 An insertion of an attribute will mean the following changes: 59 66