Add database indexes to the experiment-variant entity

[RUKAYAT-CODER]

Overview

src/ab-testing/entities/experiment-variant.entity.ts declares no @Index. Columns that are used for lookups, filtering, sorting, or as foreign keys are therefore unindexed, forcing sequential scans as the table grows. Add appropriate indexes (and a migration that creates them) so the common query paths for this entity stay performant.

Specifications

Features:

• Frequently-queried columns and foreign keys on this entity are indexed.
• The indexes are created by a reviewable migration rather than only synchronize.

Tasks:

• Review the query paths that hit experiment-variant and identify the columns used in WHERE / ORDER BY / JOIN / foreign-key lookups.
• Add @Index decorators (single-column or composite as appropriate) to src/ab-testing/entities/experiment-variant.entity.ts.
• Add a migration that creates the same indexes so existing databases are updated.

Impacted Files:

• src/ab-testing/entities/experiment-variant.entity.ts
• src/migrations/-add-experiment-variant-indexes.ts

Acceptance Criteria

• The entity carries indexes covering its common lookup/foreign-key columns.
• A migration creates the indexes and runs cleanly on an existing database.
• No duplicate/redundant indexes are introduced.

[LaTash1]

@LaTash1 has applied to work on this issue as part of the Stellar Wave Program's 8th wave.

hi, please let me do this

ℹ️ Repo Maintainers: To accept this application, review their application or assign @LaTash1 to this issue.

[devgbmuyiwa]

@devgbmuyiwa has applied to work on this issue as part of the Stellar Wave Program's 8th wave.

I can work on this issue
Kindly assign this to me.

ℹ️ Repo Maintainers: To accept this application, review their application or assign @devgbmuyiwa to this issue.

[drips-wave]

Congratulations, @devgbmuyiwa! 🎉 Your application was accepted by the repo's maintainers, and the issue is due on August 31, 2026.

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