相关疑难解决方法(0)

此查询获取您关注的人创建的帖子列表。您可以关注无限数量的人，但大多数人关注 < 1000 人。

使用这种查询方式，明显的优化是缓存"Post"id，但不幸的是我现在没有时间这样做。

EXPLAIN ANALYZE SELECT
    "Post"."id",
    "Post"."actionId",
    "Post"."commentCount",
    ...
FROM
    "Posts" AS "Post"
INNER JOIN "Users" AS "user" ON "Post"."userId" = "user"."id"
LEFT OUTER JOIN "ActivityLogs" AS "activityLog" ON "Post"."activityLogId" = "activityLog"."id"
LEFT OUTER JOIN "WeightLogs" AS "weightLog" ON "Post"."weightLogId" = "weightLog"."id"
LEFT OUTER JOIN "Workouts" AS "workout" ON "Post"."workoutId" = "workout"."id"
LEFT OUTER JOIN "WorkoutLogs" AS "workoutLog" ON "Post"."workoutLogId" = "workoutLog"."id"
LEFT OUTER JOIN "Workouts" AS "workoutLog.workout" ON "workoutLog"."workoutId" = "workoutLog.workout"."id"
WHERE
"Post"."userId" IN …

我有一个表，用于表上的多对多关系users来表示用户之间的跟随关系：

CREATE TABLE users (
    id text PRIMARY KEY,
    username text NOT NULL
);

CREATE TABLE followers (
    userid text,
    followid text,
    PRIMARY KEY (userid, followid),
    CONSTRAINT followers_userid_fk   FOREIGN KEY (userid)   REFERENCES users (id),
    CONSTRAINT followers_followid_fk FOREIGN KEY (followid) REFERENCES users (id)
);

CREATE INDEX followers_followid_idx ON followers (followid);

当我想使用与用户相关的数据创建 JSON 响应时，我有两种情况：

• 通过 id 请求单个用户，
• 通过 id 列表请求用户对象数组

用户数据对象应包含两个用户 ID 数组，一个是他们关注的用户，另一个是关注他们的用户。为了创建这两个字段，我使用了以下SELECT语句。

DECLARE follows RECORD;
SELECT  array (select followid FROM followers where userid = Puserid) AS following, …