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SQL for Self-Comments in 24 Hours
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SQL for Self-Comments in 24 Hours

MediumSQL · PostgreSQL

Problem

Write a SQL query to find users who commented on their own posts within twenty-four hours of publishing.

Use the users, posts, and comments tables. Treat comments made exactly twenty-four hours after publication as qualifying.

Output

  1. One row per qualifying user.
  2. Return user_id, username, and qualifying_comment_count.
  3. Order by user_id ascending.

Schema

users
ColumnTypeDescription
user_idPKINTUnique user identifier
usernameVARCHAR(100)User's display name
posts
ColumnTypeDescription
post_idPKINTUnique post identifier
user_idINTUser who published the post
published_atTIMESTAMPTZPost publication timestamp
comments
ColumnTypeDescription
comment_idPKINTUnique comment identifier
post_idINTPost receiving the comment
user_idINTUser who authored the comment
created_atTIMESTAMPTZComment creation timestamp
Tablesuserspostscomments
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Your question is SQL for Self-Comments in 24 Hours. Start with the requirements and the three tables in the Question tab.

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