How do the tables relate?
The connection to the MySQL database con has already been created for you. tables, a list containing the three tables as data frames that you've created in the previous exercise, is also available.
If you have a closer look at these tables, you'll see that the tweats table, for example, contains a column user_id. The ids in the column refer to the users that have posted the tweat. Similarly, the comments contain both a user_id and a tweat_id column. It specifies which user posted a comment on which tweat.
With this new knowledge, can you tell who posted the tweat on which somebody commented "awesome! thanks!" (comment 1012)?
แบบฝึกหัดนี้เป็นส่วนหนึ่งของหลักสูตร
Intermediate Importing Data in R
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