[ATLAS-3043] Unique attributes constraint at store-level

• Type: Bug
• Status: Resolved
• Priority: Major
• Resolution: Fixed
• Fix Version/s: 2.0.0
• Component/s: atlas-core
• Assignee: Madhan Neethiraj
• Reporter: Madhan Neethiraj
• Created: 01/Feb/19 01:20
• Updated: 17/Jun/22 20:49
• Resolved: 02/Feb/19 21:51

Description

Atlas data-model allows marking an attribute as unique; and on entity create/update operations, Atlas verifies that this constraint is not violated i.e. no more than one active entity of a given entity-type can have same value for a unique-attribute.

However, no store-level constraint is created to enforce uniqueness. This is likely to be due to the fact that there can be multiple deleted entities with the same typeName & unique-attribute value. And having such store-level constraint wouldn't allow this to exist.

An alternate approach is to create a 'shadow-property' at the store-level for the unique-attribute; and this property should be set only for active entities. When an entity is deleted, this 'shadow-property' will be removed from the entity-vertex. In this approach, the unique-constraint can be set at the store level for the 'shadow-property'. In addition to enforcing the constraint at the store level, it might also help in quicker entity-retrieval given typeName and unique-attribute.

Issue Links

• fixes: ATLAS-751 Add support for primary key constraint on class types