AgentSkillsCN

ecto

Ecto架构、变更集、查询与迁移。当您需要处理数据层、迁移或仓库时，可使用此功能。

SKILL.md
--- frontmatter
name: ecto
description: Ecto schemas, changesets, queries, and migrations. Use when working with the data layer, migrations, or repo.
user-invocable: false

Ecto

When to Use

  • •Adding or changing Ecto schemas and changesets.
  • •Writing or refactoring context functions that use the repo (get, insert, update, delete, queries).
  • •Creating or reviewing migrations.
  • •Optimizing queries (preload, join, avoid N+1).

Principles

  1. •Schemas: In lib/my_app/ under the context. Use @primary_key, @foreign_key_type, @timestamps; use @enforce_keys for required fields. Keep changeset functions in the schema module or context.
  2. •Context API: Expose functions like get_user!(id), create_user(attrs), update_user(user, attrs) that return {:ok, struct} / {:error, changeset} or raise for get!-style APIs. Use the repo only inside context (or dedicated query modules).
  3. •Migrations: Create with mix ecto.gen.migration name. Do not edit migration files after they have been run in production. Add new migrations for further schema changes.
  4. •Queries: Prefer from for readability; use preload or join to avoid N+1. For complex queries, consider a dedicated query module.
  5. •Verification: After schema or migration changes, run mix ecto.migrate (in dev) and mix test. Do not modify existing migrations.