Add uniqueness constraint for meta_taggings

Description

As suggested by redsummernight in the PR for AO3-2452 (in this comment), it would be good to add a unique index on (meta_tag_id, sub_tag_id) to the meta_taggings table. There’s already a constraint in ruby to try to prevent duplicate MetaTaggings, but it would be better to enforce that constraint in the database, as well.

Environment

None

Status

Assignee

ticking instant

Reporter

Sarken

Roadmap

Tags

Priority

Medium

Affects versions

Fix versions

Components

BackEnd

Difficulty

Medium

Required Access Level

None

Milestone

Internal 0.9
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