lemmy/migrations/2023-10-24-030352_change_primary_keys_and_remove_some_id_columns/up.sql

ALTER TABLE captcha_answer
    DROP COLUMN id,
    ADD PRIMARY KEY (uuid),
    DROP CONSTRAINT captcha_answer_uuid_key;

ALTER TABLE comment_aggregates
    DROP COLUMN id,
    ADD PRIMARY KEY (comment_id),
    DROP CONSTRAINT comment_aggregates_comment_id_key;

ALTER TABLE comment_like
    DROP COLUMN id,
    ADD PRIMARY KEY (person_id, comment_id),
    DROP CONSTRAINT comment_like_comment_id_person_id_key;

DROP INDEX idx_comment_like_person;

ALTER TABLE comment_saved
    DROP COLUMN id,
    ADD PRIMARY KEY (person_id, comment_id),
    DROP CONSTRAINT comment_saved_comment_id_person_id_key;

DROP INDEX idx_comment_saved_person_id;

ALTER TABLE community_aggregates
    DROP COLUMN id,
    ADD PRIMARY KEY (community_id),
    DROP CONSTRAINT community_aggregates_community_id_key;

ALTER TABLE community_block
    DROP COLUMN id,
    ADD PRIMARY KEY (person_id, community_id),
    DROP CONSTRAINT community_block_person_id_community_id_key;

DROP INDEX idx_community_block_person;

ALTER TABLE community_follower
    DROP COLUMN id,
    ADD PRIMARY KEY (person_id, community_id),
    DROP CONSTRAINT community_follower_community_id_person_id_key;

DROP INDEX idx_community_follower_person;

ALTER TABLE community_language
    DROP COLUMN id,
    ADD PRIMARY KEY (community_id, language_id),
    DROP CONSTRAINT community_language_community_id_language_id_key;

ALTER TABLE community_moderator
    DROP COLUMN id,
    ADD PRIMARY KEY (person_id, community_id),
    DROP CONSTRAINT community_moderator_community_id_person_id_key;

DROP INDEX idx_community_moderator_person;

ALTER TABLE community_person_ban
    DROP COLUMN id,
    ADD PRIMARY KEY (person_id, community_id),
    DROP CONSTRAINT community_person_ban_community_id_person_id_key;

ALTER TABLE custom_emoji_keyword
    DROP COLUMN id,
    ADD PRIMARY KEY (custom_emoji_id, keyword),
    DROP CONSTRAINT custom_emoji_keyword_custom_emoji_id_keyword_key;

ALTER TABLE federation_allowlist
    DROP COLUMN id,
    ADD PRIMARY KEY (instance_id),
    DROP CONSTRAINT federation_allowlist_instance_id_key;

ALTER TABLE federation_blocklist
    DROP COLUMN id,
    ADD PRIMARY KEY (instance_id),
    DROP CONSTRAINT federation_blocklist_instance_id_key;

ALTER TABLE federation_queue_state
    DROP COLUMN id,
    ADD PRIMARY KEY (instance_id),
    DROP CONSTRAINT federation_queue_state_instance_id_key;

ALTER TABLE image_upload
    DROP COLUMN id,
    ADD PRIMARY KEY (pictrs_alias),
    DROP CONSTRAINT image_upload_pictrs_alias_key;

ALTER TABLE instance_block
    DROP COLUMN id,
    ADD PRIMARY KEY (person_id, instance_id),
    DROP CONSTRAINT instance_block_person_id_instance_id_key;

ALTER TABLE local_site_rate_limit
    DROP COLUMN id,
    ADD PRIMARY KEY (local_site_id),
    DROP CONSTRAINT local_site_rate_limit_local_site_id_key;

ALTER TABLE local_user_language
    DROP COLUMN id,
    ADD PRIMARY KEY (local_user_id, language_id),
    DROP CONSTRAINT local_user_language_local_user_id_language_id_key;

ALTER TABLE login_token
    DROP COLUMN id,
    ADD PRIMARY KEY (token),
    DROP CONSTRAINT login_token_token_key;

-- Delete duplicates which can exist because of missing `UNIQUE` constraint
DELETE FROM person_aggregates AS a USING (
    SELECT
        min(id) AS id,
        person_id
    FROM
        person_aggregates
    GROUP BY
        person_id
    HAVING
        count(*) > 1) AS b
WHERE
    a.person_id = b.person_id
    AND a.id != b.id;

ALTER TABLE person_aggregates
    DROP CONSTRAINT IF EXISTS person_aggregates_person_id_key;

ALTER TABLE person_aggregates
    ADD UNIQUE (person_id);

ALTER TABLE person_aggregates
    DROP COLUMN id,
    ADD PRIMARY KEY (person_id),
    DROP CONSTRAINT person_aggregates_person_id_key;

ALTER TABLE person_ban
    DROP COLUMN id,
    ADD PRIMARY KEY (person_id),
    DROP CONSTRAINT person_ban_person_id_key;

ALTER TABLE person_block
    DROP COLUMN id,
    ADD PRIMARY KEY (person_id, target_id),
    DROP CONSTRAINT person_block_person_id_target_id_key;

ALTER TABLE person_follower
    DROP COLUMN id,
    ADD PRIMARY KEY (follower_id, person_id),
    DROP CONSTRAINT person_follower_follower_id_person_id_key;

ALTER TABLE person_post_aggregates
    DROP COLUMN id,
    ADD PRIMARY KEY (person_id, post_id),
    DROP CONSTRAINT person_post_aggregates_person_id_post_id_key;

ALTER TABLE post_aggregates
    DROP COLUMN id,
    ADD PRIMARY KEY (post_id),
    DROP CONSTRAINT post_aggregates_post_id_key;

ALTER TABLE post_like
    DROP COLUMN id,
    ADD PRIMARY KEY (person_id, post_id),
    DROP CONSTRAINT post_like_post_id_person_id_key;

DROP INDEX idx_post_like_person;

ALTER TABLE post_read
    DROP COLUMN id,
    ADD PRIMARY KEY (person_id, post_id),
    DROP CONSTRAINT post_read_post_id_person_id_key;

ALTER TABLE post_saved
    DROP COLUMN id,
    ADD PRIMARY KEY (person_id, post_id),
    DROP CONSTRAINT post_saved_post_id_person_id_key;

DROP INDEX idx_post_saved_person_id;

ALTER TABLE received_activity
    DROP COLUMN id,
    ADD PRIMARY KEY (ap_id),
    DROP CONSTRAINT received_activity_ap_id_key;

-- Delete duplicates which can exist because of missing `UNIQUE` constraint
DELETE FROM site_aggregates AS a USING (
    SELECT
        min(id) AS id,
        site_id
    FROM
        site_aggregates
    GROUP BY
        site_id
    HAVING
        count(*) > 1) AS b
WHERE
    a.site_id = b.site_id
    AND a.id != b.id;

ALTER TABLE site_aggregates
    DROP COLUMN id,
    ADD PRIMARY KEY (site_id);

ALTER TABLE site_language
    DROP COLUMN id,
    ADD PRIMARY KEY (site_id, language_id),
    DROP CONSTRAINT site_language_site_id_language_id_key;

-- Change functions to not use the removed columns
CREATE OR REPLACE FUNCTION site_aggregates_site ()
    RETURNS TRIGGER
    LANGUAGE plpgsql
    AS $$
BEGIN
    -- we only ever want to have a single value in site_aggregate because the site_aggregate triggers update all rows in that table.
    -- a cleaner check would be to insert it for the local_site but that would break assumptions at least in the tests
    IF (TG_OP = 'INSERT') AND NOT EXISTS (
    SELECT
        *
    FROM
        site_aggregates
    LIMIT 1) THEN
        INSERT INTO site_aggregates (site_id)
            VALUES (NEW.id);
    ELSIF (TG_OP = 'DELETE') THEN
        DELETE FROM site_aggregates
        WHERE site_id = OLD.id;
    END IF;
    RETURN NULL;
END
$$;