{ "data": { "question": { "questionId": "1877", "questionFrontendId": "1729", "boundTopicId": null, "title": "Find Followers Count", "titleSlug": "find-followers-count", "content": "

Table: Followers

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\n+-------------+------+\n| Column Name | Type |\n+-------------+------+\n| user_id     | int  |\n| follower_id | int  |\n+-------------+------+\n(user_id, follower_id) is the primary key for this table.\nThis table contains the IDs of a user and a follower in a social media app where the follower follows the user.
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Write an SQL query that will, for each user, return the number of followers.

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Return the result table ordered by user_id.

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The query result format is in the following example.

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Example 1:

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\nInput: \nFollowers table:\n+---------+-------------+\n| user_id | follower_id |\n+---------+-------------+\n| 0       | 1           |\n| 1       | 0           |\n| 2       | 0           |\n| 2       | 1           |\n+---------+-------------+\nOutput: \n+---------+----------------+\n| user_id | followers_count|\n+---------+----------------+\n| 0       | 1              |\n| 1       | 1              |\n| 2       | 2              |\n+---------+----------------+\nExplanation: \nThe followers of 0 are {1}\nThe followers of 1 are {0}\nThe followers of 2 are {0,1}\n
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